I highly doubt that we will see 10.1 in July, they will Probably save that for September when they really want to kickoff OS X.
Hopefully they will release a 10.0.4 that has some useful updates.
The main, real, and most useful update I can think of right now is a well coded finder that will run oh, say, 10 times faster than the current finder. Heck just give me 2 times faster finder. I hate having to wait in OS 9 as it is, and in OSX it is just nuts even on a dual G4. But I don't think they will have this update in 10.0.4. We will all have to wait to wait for 10.1 (or is that X.I) in September
As for DVD, there is a chance in 10.0.4 (X.-.IV), since they do have another few weeks to work on it and it will be 4 months from the initial release. (what are they doing over there at apple, still playing unreal tourney on the G4/GeForce3?