I just received an update from the Radar Chaos game I bought. They tweeked a few flight parameters and other stuff, but basically I've played every level now (but not at the most challenging levels) and it's probably one of the better ATC games I've played recently.
Air Traffic Control Game - Radar Chaos
As far as a flight simulator I'm still most impressed with X-Plane!
X-Plane
Still waiting for the next Microsoft game: Flight.... waiting... waiting... waiting...
3.5