Originally Posted by Dolfy
What's this Cyanogenmod 2.2 that you guys are talking about?
In simple terms, the Android operating system is open source, so anybody* can get a copy of the code, modify to their liking, and install it on their phone. Cyanogenmod 2.2 is one of those modified versions - of Android version 2.2 - that happens to have a very large user base, so any problems are quickly found and remedied. So since older phones like my Hero may only have Android version 2.1 (or even 1.x) on them, and the carriers aren't planning on officially supporting the newest version, many people install Cyanogenmod 2.2 to have a lot of the features of the latest and greatest phones. Cyanogen also comes with a bunch of tweaks to boost performance and make your phone more customizable over a "stock" Android version.
*Anybody can do it, but not necessarily should do it.
The larger the user base, the more stable the release will be.