The only niggle I've seen is from folks who want Apple to include a full gig of RAM. No matter--I've already got two 1 GB sticks on order.
I thought about a prior generation one briefly--but the built-in AE and Bluetooth, along with the (much improved) graphics card, faster processor (I know, not a huge difference from 1.8 to 2.0), bigger HD's, etc. sold me on the current ones. And the 20" seems like a good way to go--bigger HD, screen, better resolution.
I'm going to pick it up today--the RAM should arrive tomorrow.