Its so damn tough...I'm looking for a new iPod though...
Unless there is an announcement for an SDK for iPod, then iPod would be way off-message for WWDC - this is a developer's conference, not a consumer products conference.
I don't think that Apple can afford to not update their iPods this fall though, but that doesn't mean that they will pull the announcement forward to step on the iPhone frenzy. For the past the past three years, Apple has updated much of their iPod product line in the fall, I really don't see them breaking their pattern to announce a new iPod at WWDC.
Yeah, even if you can wait the 3 weeks until WWDC, there's no guarantee any hardware updates which are announced will actually be available and shipping immediately. Hell, we may see a ton of new hardware, yet Jobs might announce that it will all be shipping in conjunction with Leopard in October.
I don't think three weeks is that unrealistic, particularly when a lot of the product line could use an update. If you need it NOW, as in that's what your job needs and you don't have something to use in its place, then buy it now. I've done very well in waiting, except for when I lost my nano late last summer. I knew a nano update was highly likely a month later with double the capacity for the same price. I wasn't going to wait a month without having a compact player, so I just bought a new nano right away.