I don't understand how this can be voted negative. If this happens in the next iMac revision, and hypothetically, Apple decides to use a 5000 series Radeon video card on the high end iMacs, literally everything will finally be considered "high end" on the "high end" iMacs, which is where most of the criticism against Apple lies.
The only thing I would be left to complain about would be lack of USB 3.0, given that a major refresh sometime this year would last into Q4 2010, in which case many new peripherals will support it.
On that note, I would be somewhat upset if the new iPhone does not support USB 3.0 connectivity, having an iMac refresh coincide with its' release.