Hyperthreading alone is going to scale before you take Turbo Boost into account. I'm wary of even getting a Core 2 ULV or CULV when I can get Arrandale. Remember it's 2010.
Yeah, but I've just bought the top of the range 15" and I can't fault its performance at all, so as far as I'm concerned, sitting around waiting for the next best thing is pointless because there's always something round the corner. Another thread like this'll be popping up in October!