"The developers at XDA have been porting Android to the HTC Touch Pro 2/Tilt 2 since February. Yesterday they reached a new milestone of usability -- SOUND FINALLY WORKS!
The newest build sports Android 2.2 FroYo and works on both CDMA and GSM phones. The build is not a full ROM, but rather uses the haret SD boot method, leaving Windows Mobile intact. There are still some features to be developed (Bluetooth, camera, OpenGL ES rendering, and the battery meter is a little quirky) but overall this build is very usable!
More at XDA:
http://forum.xda-developers.com/showthread.php?t=627997