essentially the same as it was 24 hours ago. I'm not sure what new features weren't there before. The hype on the box is 99 cent songs from the Apple Music Store (which I definitely had), rendezvous streaming to mac and windows machines in your home (which I've been doing for a while as well), encoding AAC music (already there), and importing on-the-go playlists from the iPod (which doesn't work with my old model). So if iTunes is the only thing you care about, save your money.
a bunch of new effects and titles were added. Most of them are gimmicky, just like before, but I guess more canned stuff in your library is always better, because you never know when you're going to need it. Clip editting is better. Still not as nice as say, Final Cut, but that's to be expected. Its pretty much the same program as before, but faster and enhanced with niceties. If you use iMovie a lot then this is worth it. The biggest disappointment I have with it right now is there's no way to composite one movie inside of another. Some of the transitions do this temporarilly, but I really want to be able to do a simple Picture in Picture effect, and I can't.
I expect not that many people use iDVD. If you do, then this is worth the upgrade alone. As with every new version of iDVD, you get new themes (and all the old ones are still there, avoiding the dumbass mistake they made between iDVD 1 and 2). The new themes are nice, but the real killer is the DVD Map. The box bills it as just a way to get an overview of your project, but its actually useful as an editing tool. You can drag files into it and hierarchically assemble a DVD, sort of like in DVD Studio, but a whole lot easier. Also, motion menus and sound loops are no longer restricted to 30 seconds (though you only have 15 minutes worth of motion media to use on your entire DVD, you can split that up however you want). This is cool, because it means you can put whatever song you want in your menus on loop. You also get 2 hours of footage on a DVD now instead of just 1. That's probably worth it right there. That's like a full feature length film. Oh, and you get "cinematic transitions" on your slideshows, but I never actually make DVD slideshows... who knows, maybe I'll start.
As anukul said, "now featuring Sucklessness!" BONUS!!! Its definitely like a zillion times faster, and though not as snappy on my 1Ghz G4 powerbook as it was for iSteve in his keynote demo, it is quite snappy and usable, something that definitely wasn't true before. Scrolling through a couple thousand pictures isn't quite as fluid as scrolling say a webpage, but its definitely workable and usable. Also added was the ability to rate pictures for generation of an album sort of the way you rate songs in iTunes. And you can play a slideshow with a playlist for music now instead of just one song repeating over and over again, which is so obvious a thing to do that its ridiculous it took this long. But hey, better late than never. You also get new slideshow transitions, though not that many of them. I'm pretty surprised they don't just give you the iMovie library of transitions.
The killer app of iLife. Actually, I'm not sure if that's really true or if it just feels that way because its the new thing and everything else is just and upgrade. But after only 24 hours, it feels like something that is worth paying the $50 for alone. Its not quite as cool as iSteve implied. There seem to be a lot more electronica oriented loops than other stuff. Kinda curious what's in the Jam Pack add-on, and might go buy it later. I still don't have a USB<->MIDI adaptor yet, so I haven't tried any of that stuff. But I'm extremely amused by what you can do with the included loops alone, and would probably have paid $50 (basically a playstation game) for that alone as well.
So anyway, yeah, I think its worth it.