Android 2.2 on the T mobile G1 is out via cyanogen mod 6.0.0 RC1. It is amazing that the G1 was able to get Froyo before most of the high end phones such as the HTC Droid Incredible, Samsung Galaxy S or the Evo 4G. Keep in mind that this is not the official release and is still in the experimental stages of its development, however in the next few weeks we should see a full release from him.
The mod is also out for multiple other devises such as the mytouch 3G and the Nexus one.
You can grab the Rom from his website and while your at it buy him a beer.
http://www.cyanogenmod.com/
Also if you are not rooted check out this rooting tutorial, it very helpful.
http://www.youtube.com/watch?v=BJtKAFs6Zwk
and
This Wiki will answer all your questions about how you install CyanogenMod 6
http://wiki.cyanogenmod.com/index.php?title=Main_Page
Guys don't be scared of going to cyanogen forums and asking for help there are people there that are more that welcome to help you.
I am not responsible for anything that you do to your phone.
Again a big thanks to cyanogen and his team for making this happen.
