The keynote to MACWORLD is tomorrow. WWDC (worldwide developer's conference) happens later in the year, and traditionally doesn't feature much in the way of interesting product announcements, though that has changed in the past couple of years.
Leopard, the new OS X, has no fixed release date, and no one agrees on when it could be coming. For all we know, they could drop it on us tomorrow. A phone has been rumoured, but that's 50/50 at best, a new computer model is a pretty good guess, there's a good chance at a new iPod, and displays as well, and finally, expect new wireless routers, er, sorry, AirPort base stations. Maybe iTV, but I still can't figure out why I want one of those, so I don't care.