Exactly.
Current iMacs exceed the power need of 90% of the users.
The bottleneck is the hard disk, try putting a Intel SSD inside an iMac and you'll see Photoshop loading in 4 seconds, Mail in 1 second, ecc.
Sometimes nerds don't realize that people out there doesn't care about quad-cores or stuff like that. They care about how the computer behave in real world usage.
The challenge now is optimizing software and squeeze all the juice out of the current hardware (64bit, OpenCL, GCD, etc.).
Now if only they could make Cocoa work with C++/C# etc without using Objective-C.