After personally experiencing what vibration reduction technology is capable of, I'm not really interested in spending good money on a tele without it, unless of course I can get it for a song. Class-D is to amplifiers what IS/VR is to lenses--it's the future.
Until you can afford the big mutha, your photography
in general might be better served by Canon's consumer-grade (i.e. made of plastic) telephoto zoom lens, the 70-300 f/4-5.6 IS. I don't know your shooting habits, but when I go out it's usually for hours. After a few miles of walking, my father's 80-200mm f/2.8 starts wearing on me.
Also... it's more of a thought experiment since I haven't actually made the comparison in reality, but when shooting handheld, a 200mm lens at f/5.6 w/IS has the potential to produce sharper images than at f/2.8 w/o IS. Camera shake ruins a picture completely, but a slightly motion-blurred subject can often be desirable.
Then again, if you're only interested in low-light shooting or always shoot from a tripod, forget everything I wrote
-Frank