Condo's are even more location sensitive than houses in my opinion, especially since your limited with what you can do to spice them up. Like a house, you can redo the exterior (think shingles vs. stucco), add a bathroom, garage, pool, deck, etc. Condo? repaint the walls, new appliances, mini-bar, if the HOA allows... But like a rj said above, they're good for a quick flip if you play it right.
Condo's in most American cities located downtown will usually hold there value okay. Though there was a big rough patch for a few years there but a lot of them have bounced back. The suburbs however, different story.