Matt Laur , Feb 21, 2012; 09:29 a.m.
Avoid the super zooms (especially those that are stopped down past f/5.6 at the long end - you'll have autofocus trouble to go along with having less light to use). Since you already have the 18-55, I think the 55-200 is a sensible and modestly priced next step. But depending on what you're planning to shoot, a 70-300 might make more sense, and they too can be had for pretty reasonable prices. The gap between 55mm and 70mm isn't going to hurt you too badly, but the 70-300 is going to look a lot better at 200mm than the 55-200 is.