According to Googling Google, that option will be available starting tomorrow, from Anne Wojcicki, founder of 23andme and the wife of Google co-founder Sergey Brin.
I won't say it's not tempting, but I don't think I would do it, even if it cost $50 (a not-trivial but affordable sum for me, unlike $999, which is both not-trivial and not affordable). I think it would probably cause more unnecessary worry than potential benefits. If I'm going to die from some dread genetic disease before I accomplish what I want to accomplish in life, I don't think I want to know that ahead of time. People tend to anticipate that things will be worse than they are when they actually experiencing those things. If I make it to the age of 80 or 90 in good health, I might do it then. (Although that might reveal things about my children's genetics that I wouldn't want to know.) That would be, in, oh, 2059-2069, by which point, I imagine this sort of thing would be much cheaper.
I absolutely want no part of something like that - I'll wait for the end of the story to learn how it comes out (I don't read spoilers either).