Thanx for the help, guys!

To take the questions in order (most of this has been answered correctly, but anyway...)
As Havelock said, no release date for the slimmer 60 GB version --- I believe on this side of the pond we just recently got the 60 gig in the first place (a few months after I bought my 30 gig --- grrr!)
You can add a track to the now playlist list alright (just select the playlist/now playing/go back to the track you want/push add to selected/back to now playing and it'll be added), but if you want to keep it in the playlist for future you have to Save As Playlist. To my knowledge there's no option for changing the order of the tracks.
Play Now: well, if you highlight a track and hit the PLAY key, it will begin playing immediately
PLAY MODE is available through the player options. Offers Normal, Shuffle, Shuffle Repeat, Repeat Track, Repeat All, Track Once
COLLAPSE No I don't believe this is available, however you can select VIEW DETAILS while the track is playing to get all the relevant details, such as album, year, genre, duration, number in playlist etc, or LOOKUP ARTIST which will give you a listing of all albums by this artist on your player, from which you can then select if you wish
CHANGE ORDER Other than the above PLAY MODES, no
TRACK DETAILS Yes, through VIEW DETAILS
REMOVE Yes, this is available. You can either remove one track from the playlist, or all tracks. In fact, when in NOW PLAYING mode, if you want to make a new playlist, you HAVE to remove all, otherwise your new playlist just gets appended to the one playing.
REMOVE ALL Yes, as above
(It should be noted that REMOVE TRACK or REMOVE ALL do NOT remove the track from your player, just the current playlist)
SAVE AS PLAYLIST Yes, the ZVM gives you an alphanumerica input keyboard with which you can name your playlist anything you want. If the name is longer than can be displayed, it will scroll when you select it.
Finally, MPEG2 playback, as the guys have told you, is supported. One thing about the ZVM is that some videos have to be converted before they can be used with the player, but Creative bundle a video converter with the software.
Screen outside is not too visible: even when I'm walking to work and want to see how far a track has got, I have to shade it with my hand in bright sunlight to see it, but overall the screen of the ZVM has been acknowledged generally as one of the best, if not THE best, around. Video playback is normally crisp and uninterrupted (of course, that does depend on the video...)
Hope that helps!
TH