It's only half a second, but...
You all know and love (I hope) intellisense, and so does the Java developers. It's already became a crucial part of any respected IDE.
One of the best things in VS.NET intellisense is its rapidness. The moment you type “.”, you get the members list. This way one can type a whole line of code simply by typing “.” and TAB's. Sounds trivial, isn't it?
Well, not always. In the Java IDE's I know (WSAD and WebLogic Workshop), there is a small delay after typing “.” and before the list appears. Something like half a second. This does not sounds too much, but it's really annoying. When one is in a “coding trance”, then one does not want to wait for the IDE to help him.
IMHO, it is better to omit the intellisense than to make it in a way that delays the developer.