The hack proves that Android 2.1 can work on first generation Android phones like the T-Mobile G1.
Called Cyanogen, the upgrade is not for the feint of heart and has the very real potential of bricking your phone. However, if successful, HTC Dream, Magic and Sapphire (T-Mobile G1 and myTouch 3G) users could have most of the features of the Nexus One on older, slower Android phones.
What's NOT included that you'd find on a Nexus One:
* Launcher2 (too clunky for these devices)
* Stock Live Wallpapers (LWP support is there, but may not work with all LWP apps and/or performance may be bad)
* Facebook (install from the Market, contact sync works perfect)
* Google Voice (install from Market, push notify works perfect)
Engadget notes that the upgrade downloads are so popular that the sites that host them are experiencing problems.
Most users should take a pass on this hack but should be happy to know that Android 2.1 can be ported to their phones.