yeah you can put your own videos on (even DVDs), but not with apples software. For mac i got handbrake to encode mpeg4 and H.264, heres a couple good links
http://diveintomark.org/howto/ipod-dvd-ripping-guide/ For mac
http://www.engadget.com/entry/1234000027063418/ for windoze
i dont care much for the video in the new iPods, but the 20 hrs battery and the really thinness makes them a pretty sick deal for sure... and i have a nano (i got it for free a month ago, wish i had waited and picked the new iPod)