I created a NTSC DV-AVI widescreen video (Share > AVI > DV-AVI) 30 seconds long and attempted to play it back in Windows Media Player 11. The player hung and I had to soft reboot Windows XP. I created some other DV-AVI videos and they also caused WMP to hang. Only a short 5 second video could be played back, but only after a lengthy pause. The properties of the video according to WMP had blank information about the characteristics of the video. The videos played without any problems when brought back into PrE10.
There is no problem with DV-AVI videos created with PrE9.
My thinking is that PrE10 has a problem writing header information in DV-AVI files.