Please test with newer nightlies if I haven't though. The worst you'll ever get is a bootloop and you can always reflash the nightly to revert back.
So jabbawalkee made this theme... http://forum.xda-developers.com/showthread.php?t=959065
And then I ported it for JPY/KB1 roms... http://forum.xda-developers.com/showthread.php?t=971076
And then CM7 was released, and since the original theme was made for CM7 it was a pretty simple port. I don't have a lot of time right now, so I'm going to keep this short. The theme isn't completely done, and I'm still trying to get everything to work before adding it in, but overall everything matches pretty well.
Yes, I did just take the screenshots from the original thread because this IS what it looks like
PLEASE PLEASE PLEASE DO NOT REQUEST THIS FOR THEME CHOOSER OR I'LL EAT YOUR UNBORN CHILDREN. THANK YOU.
SINCE v1.4, APPS ARE INCLUDED IN DIFFERENT PACKAGE. Please don't hate me for having to flash 2 things.
Base Theme v1.6
NEW Apps v4
Q: I've flashed this theme and the pulldown toggles are still green.
A: That has to be manually changed under CM Settings -> Interface -> Notification power widget -> Indicator color
Q: I've flashed the theme/ restored a backup and my contacts and phone are missing.
A: Reflash nightly, reboot, and reflash theme. They should be back. If not, flash this.
Q: THIS THEME DOESN'T WORK WITH [insert other GB rom here]!!! WTF? that's f***ing stupid, they're both Gingerbread! who makes a theme that's compatible with a single ROM? ffs
A: U mad?
Q: How do I get my phone to look like the screenshots?
A: Info is here
Q: Why weren't the first 2 questions actually questions?
A: ...shut up