I don't know any more than the next guy on here, but I had an interesting thought this evening. Apple confirmed an update to the Mac Pro in 2013, but didn't mention the iMac. What if Apple were planning on merging the two lines, like an iMac on steroids with the highest end processors and full expansion possibilities. Apple is trying to make everything as simple as possible now, even things that maybe shouldn't or don't need to be simplified, just look look at Final Cut Pro 10 and even iTunes now. Sure it's unlikely, but anything is possible.