I too feel like an idiot savant sometimes.. in a lot of ways I am... I'm terrible at languages and reading comp and rote memory... but I'm way above average at puzzle-solving and being about to grasp all of a problem and find a working solution to it.
I know the feeling. If I could shake my ADD like symptoms, and improve my notoriously bad memory, I'd be happy.
Generalized depression and apathy don't help either. :/
Anyhow, it doesn't matter what your IQ is really; it matters what you do with it. If someone with a IQ>=150 does nothing but attempt to erect a facade of normalcy all the while growing more and more contempuous for the (abnormal, in his/her eyes) world around him or her that IQ isn't really benefitting them much.
I agree with Edison who said, "Genius is 99% perspiration and 1% inspiration."