Is it possible to connect two (or more) android devices via USB to the dev machine and debug programs on both devices at the same time? I am trying to do this with an Atrix and Nexus One with no luck.
I couldn't find much documentation about this leading me to believe that it isn't possible..
You can certainly attach two Androids by USB to the same dev machine, and you can debug both of them.
If you are using adb, then you have to specify which Android you are debugging, and can only debug one at a time.
If you are using Eclipse (Helios), you can select the device in the Android Device view, and see output in the Android Logcat view. And I observe that if you select Android A then Android B a few times, you get intermingled Logcat output from both devices. I don't know if that's the design behavior, and it may not work the same on all versions of Eclipse, but it can be helpful.
Another approach is to monitor one device in Eclipse and the other in DDMS.