People always seem to be comparing the two. Having lived in Brooklyn for six years and now SF for three, I do see the similarities. However, just two days back in Brooklyn has made a few differences very clear. For one, there is *far* more diversity in Brooklyn. It's actually not even close. Then again, I don't consider SF to be diverse at all. I have been in Brooklyn for a little more than a day and I've already seen so much more than San Francisco has to offer. People here are simply all over the place: different races, ages, interests, styles. It's a kaleidoscope of folks. SF is exactly the opposite. The Mission = tedious hipsters. The Marina = Hoboken-esque frat-boy sucks. Noe Valley = young, hip couples.
I realize that I might sound bitter. But I'm not. I absolutely love San Francisco, but that's based primarily on the landscape, the people in my life and the small life that I've built there. However, it is absolutely *not* the mecca of diversity in the United States. You'll find that right here in Brooklyn, where certain areas may cater more to a certain crowd, but almost all sections of this great borough offer up much more than the local flavor.
Strangely enough, I have no desire to move back. But man is it a wonderful place to be.