IQ, what does it really mean?

We all know what the regular IQ test is like (well kinda for me. My mom bought one for me from Barnes & Noble when I was a kid and I found it really easy, even more so when I found out the answers were in the back of the book :P ) but as the book talks about is it really to gauge how smart or dumb a person is? I found out that it's reading, math and comprehension skills and how well a person can grasp concepts and ideas but it never takes into account any other kind of aspects of intelligence. Yah a person may score extremely high on the IQ test but not be able to hold a conversation with a "regular" person, they might not be able to assimilate into society because they are to smart. The best example here I can think of is a TV show (sadly). I watch Bones and in the first couple of seasons they had a young man on there playing the character of Dr. Zack Addy and he had an IQ in the crazy high range like 180 or something. But they wrote the character as having a tough time just trying to make simple conversation that didn't have to deal with work, didn't get any jokes people cracked, basically had no sense of humor and dealt in absolutes. Sure he was smart but he wasn't life smart as I call it.
     I really liked Gardner's Theory of Multiple Intelligences in how it doesn't relie on test scores to base a subjects intelligence but rather research in many different categories like child development, studies of brain damaged people, and studies of exceptionally talented people (I would guess savants would be placed in this one). A savant is a prime example of other intelligence besides the basic ones we test. They can be really smart at one thing like music (as the example in the book). They can hear a tune just once and play it back without any training of any sort but according to regular IQ tests they are in the  mentally retarded range. But I would like to say if one is mentally retarded how do they preform such a feat and play beautiful music? How about people that study other people and their emotions (like a profiler)? They can be really smart, above what we think day to day stuff, and predict what criminals are going to commit what crimes and where they will strike next. Is this not a kind of intelligence? Another is someone that can read someone's emotions and play on a persons strengths and weakness of that. The only thing that is coming to mind is some kind of con-artist like the people that say they can talk to the dead. Is this still some other form of intelligence? The list can go on and on.
     I wish the book gave more examples of Gardner's Theory and not just a list of the intelligences he came up with. It would have been excellent reading and quiet captivating if they had.