I think the Santa Rosa platform (inc. Core2) is currently undergoing its final curtain call, I can't see Intel increasing Core2 speeds any more than they are now. My thought is that Apple will adopt Arrandale at Xmas.
I would expect the new processor architecture, OLED is questionable. Along with the faster processor speed increases it would also make sense for them to include the new USB and possibly Firewire standards. BD would be nice, but I don't expect it!
OLED is probably not until 2011. It's a bit too pricey right now, even for a Pro laptop. Arrandale is coming as well but it's 50:50 between before the New Year or after it. When we get 22nm CPUs and GPUs with affordable 1.8" SSDs and super-thin OLED screens in every laptop, then will be the time to buy again