This is an adaptation of audiotest.html, I've only got an MP4 video file at the moment, hence this is broken on Firefox/Linux and Opera/OS X.
This was to test a problem on rhythmaction not working on iPad, I assumed it was related to iOS 4.2, and kludged a fix using the controls. However, I've not been able to replicate the scenario here, other than in the case where the video tries to play without any user input. Maybe there'ss something nasty in the rhythmaction code that makes iOS think the video is starting in that way?
Here is a similar video element but with no controls, but a JavaScript button to start it with an onClick handler
Here is a similar video element but with no controls, but a JavaScript button to start it with an addEventListener handler etc
This video will autoplay using JavaScript - DOES NOT WORK ON IPAD, AS EXPECTED. On iPod Touch, doesn't autoplay, but you always get some controls, so it can be played manually.