It's not just Gmail
No matter who you use, your email passes through somebody else's computer. Even within a single company, the admins may have he right, by company policy, to look at your mail.

If getting mail from Gmail scares you, then you should also worry about Hotmail, Yahoo, and all the other such services.

The only thing I've heard that creeps people out about Gmail is the ads that they insert on received mail.

I love Gmail. It's much better than any other web-mail service I have used, and I have used the major free ones, and some of the private ones.

It's not just Gmail
People simply don't know and don't think, and unless there is perceptible consequence which they can't ignore, they will choose to keep not knowing and not thinking. Google had the misfortune of awakening people to a fact they didn't believe was worth thinking about before. The classic reaction is, of course, to punish the messenger.

for me it's the advertising
I don't want advertising inserted into email I send or receive, it's that simple.

So most likely I'll add gmail to my spamfilter soon and will simply not send to anyone using it.

It's also my one pet peeve with Yahoo and Hotmail but at least there the ads are limited to an area at the bottom of the message and they're not targeted and formated to make it appear like I put the links there as a recomendation to the reader!

It's not just Gmail
The problem is not the spectre of BAD EVIL CIA and FBI hanging over the world ready to take power like sites as the ones quoted seem to want to convey, but the way Google is creating themselves a commercial empire in which it will soon be impossible to use the internet in any way without paying homage to them.

It's already getting to the point where unless you pay Google for a good search rating your site won't turn up in 90% of web searches, and in none that are on common terms (unless the searcher uses a real search engine rather than the Google one which just pulls up entries based on money paid by the site owner).

Google will also have the same power over your GMail account that companies building site blocking software have over their customers browser.
If you get sent an email recommending a product but Google is paid by a competitor, will it arrive?
Or if it arrives, who is to say Google will not silently and transparently replace my recommendation with that competing product?

We have their word on it maybe (or their subscribers do, outsiders are fair game), but we also had their word that search results would never be influenced by payments to Google yet clearly they are.

for me it's the advertising
well, its quite funny that gmail doesn't insert (at least in my case it hasn't inserted any so far) in outgoing ads.
Yahoo! does.

With gmail release, I shall stop using Yahoo! mail because I don't want to ask every single person I mail, "Do you Yahoo?"

The ads in gmail are not a part of the text area proper. They appear of the right of the screen, much like ads on the Google Search page.

And of course, Google doesn't, or hasn't so far done this.

But if you are worried about the privacy angle, don't send mails to google.

P.S. I don't use hotmail. The 2MB mbox gets spammed out of action in less than a day.

Still don't get it
I must have slept through when advertising became this horrible, evil thing threatening to destroy us all. Last time I looked, on my shelf at work I had this book that listed businesses by keywords - and if they wanted a bigger, more prominent ad in that book, they had to pay money. It's called the 'yellow pages'.
If you want something for free, then you just have to accept that someone somewhere has to pay for it. If you pay for your own e-mail account, then you don't have to worry about the ads. Pretty simple. If you don't like the idea of the service, don't use it. As was mentioned, it doesn't put ads into messages sent to you, unlike every other free e-mail out there.

Still don't get it
The yellow pages are a great example of how advertising can be free, useful, and unobtrusive. Kinda like Gmail.

It's not just Gmail
"Google ... just pulls up entries based on money paid by the site owner."

Do you actually have any evidence that's happening, or is this just FUD?

Yes, the results that get clearly marked as "Sponsored Links" are paid for, but I'm pretty sure the rest are not influenced by $$.

Old FUD
Every once in a while a company enters a global market which has been divided up among a bunch of large companies, and suddenly pundits of all flavors find out that it's been topmost issue for such a long time to warn people of underlying dangers.

I know, conspiracy theory, yadda yadda. And it's surely without precedence that expert voices were being paid by Yahoo or Microsoft to spread objections against the new kid on the block ...

for me it's the advertising
"I don't want advertising inserted into email I send or receive, it's that simple.

"So most likely I'll add gmail to my spamfilter soon and will simply not send to anyone using it."

You're confused. GMail doesn't insert advertising into anybody's email, ever.

The only ads in GMail are shown down the side of the GMail user's screen. Unlike some other webmail services, GMail leaves the mail itself entirely untouched.

I agree...
Andrew, I agree with you. I really don't understand how a person will not want a GMail account. You see ads everywhere. Hotmail is full of them. Also Yahoo (not paid version). what do people know what Hotmail or Yahoo are doing with you e-mail messages? Google is the first that is saying something about doing anything with your messages. But maybe others are doing it without even saying it.

I am desperate! I want my gmail account now...

There is a reason...
...that Gmail represents a real threat. It doesn't have to do with Google tracking your email, or scanning the contents and presenting context-sensitive ads. It has to do with the fact that an external attacker can create an AdWords campaign that allows them to extract arbitrary information from between two people, as long as the message recipient has a Gmail account. As I postulated on http://www.brendonwilson.com/profile/000158.shtml:

"Well, you have to consider how Google's advertising system, AdWords, works. Anyone can get an AdWords account with Google, allowing them to create a campaign that will display a specific advertisement to users when they search for the keywords associated with the campaign. For example, I created an AdWords campaign for my book, associating a simple text ad with the keywords "java", "p2p", and "jxta" - whenever someone entered those words into Google, they saw my ad.

Google's AdWords system provides an advertiser with reports on the ad campaign detailing the number of times an advertisement has been displayed and the number of times a user has clicked on the ad. Though the AdWords administrative interface doesn't report who saw my advertisement, throwing GMail into the mix makes this irrelevant. In order for me to be able to spy on a GMail user, I only need to carefully craft an AdWords campaign with a very specific set of keywords, and monitor if anyone ever triggers the display of my advertisement. This technique allows any user, not just Google, to effectively monitor GMail-based email communications, and only requires one of the parties (preferably the recipient) to be a GMail user.

Is this attack practical for general-purpose spying? Probably not. It's unclear at this point whether GMail uses email headers that would permit this attack to be specific to an email address. It's also unclear whether Google will filter out proper names to limit the ability of an attacker to target a particular person. However, an attacker could conceivably use knowledge of their victim to tailor the AdWords campaigns' keywords to be arbitrarily precise."

It's not just Gmail
First of all: If you're kidding, please don't. People actually believe most of what they read.
Ok, now on to my responce.

Google does not, in any way, tamper with its search results. There was a court case that required them to remove two results from a specific search, but for that search they put the two links that were removed at the bottom of the page (so you can still get to them just as easily).

In general, Google tries to be as user-friendly as possible. They don't use flash ads, or banner ads, or pop-up ads. They use text-only ads, in a different color, on a sidebar where they can't be confused with search results. These text-only ads are paid for by the advertisers, but their standard search results are not.

Google had a scuffle with China awhile back because they refused to change their content to China's government's standards.

Now, on to Gmail. Google does not tamper with your Gmail. It does not put an ad for itself at the end of every message you send (as Yahoo and Hotmail (I think) do), and it does not use flash ads (as Yahoo does...I can't speak for Hotmail).

Google displays text-only ads to the side of your email messages as you read them, and does not ad these to incoming or outgoing mail. These text-only ads are based on the content of your email, but they are automatically generated by a computer. No human at Google reads your email.

I hope I didn't offend anyone with this, I just tend to get...defensive of Google.

Oh please.
I didn't you were part of the tinfoil camp.

Google does not place search results by money; only the "sponsored links" stuff is paid for. If you can substantiate any of your claims, we can talk further.