Aah, my brother has a 4 year old 600MHz G3 iBook that was a refurb to begin with, and it's still getting things done. If that works ok, a new iBook should serve you well for a while yet.
And yes, something that'll make yours feel oh-so-terribly-inferior will probably come out at MWSF--that's the way it ALWAYS is. Just don't pay any attention to what's new for a while, and you'll be much happier (that's what I do!).
Plus, even if super-fast Intel iBooks did come out then and ship immediately (yeah, right), it'll still be months before anything but a couple of apps are native, so it'd still probably be slower than your PPC one for a while yet. The next, probably next two releases of the MacOS at the minimum will run on PPC (probably more than that even if the available software offerings shrink--remember that Tiger is still supported on Macs that were 6 1/2 years old at the time it was released, and can be forced to run on much older), so I can't imagine a current model being anything but a worthwhile computer until at least the end of the decade.
