Related link: http://www.plazmic.com/en/download/index.shtml
You’ve been able to download new themes for your BlackBerry for a while now. The O2 theme is extra polished:
Here’s an NHL theme that someone has created for the soon to be released 8700c.
The Plazmic kit also comes with a utility to transcode Macromedia Flash files into SVG for use on the BlackBerry.