I debated that too, i am using the other low powered home iMac now, so i can't do jack crap on a 2009 21" base low end model. but figured to order, wait, have bill sit, delete hard drive, pack it up, return it and wait for refund just to do it halfway again is more of a hassle. plus once a 27" display is on my desk i won't want to take it down.
* hope the assumed redesign means antiglare edge to edge glass panel and thinner iMac, but same pedestal. I say so because I want the i360 Raindrop turntable pedestal holder thing, in which it fits the current iMac