Apple's new fusion drive might not deliver the punch we might expect. Work provides me with a one year old MacBook Pro with an i7 cpu. It should be a capable machine, but I found it to be slow and incapable of running many apps / having many files open without becoming unstable (memory management problems, pinwheel of death, the OS getting confused about which app is in the foreground, video display not being updated).

So IT replaced the hard drive with a solid state drive and upgraded to the latest OS. Yes, it boots faster, but all of the other slowness etc is still there. In my case a super fast drive did not improve performance, so I would wonder about how fast the new iMac will be, given that an almost new MacBook Pro is not a whole lot faster than a low end, 10 year old Dell box running Win7.