I just watched part 3 of mobileburn.com review of the Droid X and at about 6min20sec in it mentions it "doesnt seem to play avi's. Can anyone at Androidcentral confirm this?
YouTube - mobileburn's Channel
YouTube - mobileburn's Channel
In the BGR review, it said the phone support avi's. here
avi is a packager, divx/xvid is what you're looking for. Videos can be converted easily on a pc to the right type using a program like handbrake. The samsung moment and Galaxy phones will support avi/divx/xvid. None of the HTC phones do, and neither do the Moto phones currently.
nice, divx and xvid support ROCKS. i hate reconverting my movie library to load on my phone, way too much effort.