I think it is a given that the next 15" MBP will have sandy bridge inside. What I would be curious about is the performance difference between the current arrandale i5 and the sandy bridge equivalent i5 (adjusting for GPU differences of course). I guess if the performance difference is more than say 15% it seems like a no brainer to me that it is worth waiting for sandy bridge. Anyone have an idea of what order of difference we can expect between arrandale and sandy baby?