The one thing you shouldn't do is blame a device for being incompatible with video (again, audio/video) files that you've created designed to be played on another device like an iPhone or iPod touch.
I didn't create them specifically to play on a iphone. And they play on all my other devices and computers.
And I will blame the device for being way too fickle about the specs your
mp4's need to be in order to play back. Seems like an excuse for poor software to me.