Define most advanced?
It's definitely a language used on an enterprise level for lots of huge applications. If you mean used by lots of advanced programmers then yes - most decent programmers that I know of know at least the basics of it. It's not something like VB
which has turned into a bit of a running joke in the industry!
If you mean most advanced as in hardest to learn - then no. It's actually pretty easy to get to grips with initially, but believe me you can end up frying your brain with some of the more advanced aspects of it if you're not careful...