The biggest issue I have with iMacs is the way they make your monitor obsolete when your computer is. It's a very smart move by Apple, but painful for the consumer market roped into buying an iMac.

Sonnet has a better idea, I think. Strap your Mac Mini to the back a monitor of your choice. Seems so obvious once you see the product.

Sonnet: MacCuff mini:

Sonnet's MacCuff™ mini mounting and security system frees up desk space by securing your computer to the back of an LCD display (or mounting it under a desk or table) while allowing full access to its ports and disk slot. How do you mount a computer to the back of a monitor? VESA mounting holes on the back of many LCD displays provide an ideal spot to attach MacCuff mini.

Smart idea, especially the VESA mount integration. My only worry is heat; our Mini G4 gets awfully hot after so much as a bit of Flash action, much less something like WoW. Still, this is very tempting at $50.