It needs to have good code completion support, debugger, and a nice way to browse code (click to go to documentation).
Since I got spoiled by Java IDEs (Eclipse), it would be cool if it supported refactoring, reference search and some form of on the fly compilation, but maybe I'm asking too much.
So far I tried Eclipse C++ plugin, Qt Creator and Code Blocks. Eclipse plugin feels sluggish, Code Blocks has much worse completion then Qt Creator and Qt Creator is great for Qt stuff, but kinda hard to use for free form projects.
What are other options and firs hand experience with them, since trying something for few hours and using something on a daily basis are two different things?