First, you'd need to start with defining what you mean by "how they do". Some people seem to have the expectation that anyone prodigious needs to change the entire world or win a top prize or they have failed. That is unfortunately the standard that to often is put on prodigies and there is no need to repeat that on a forum that is supposed to be supportive of gifted children. Similarly, I don't find a lot of value in trotting out "I once knew a kid who was accelerated and he was a weirdo who killed himself" type of stories.
As far as career counseling there has been more written about this recently I would suggest Googling gifted career multipotentiality and you will probably find a bunch. I don't at all agree there is no possibility of getting career advice and that's one reason why we've worked to connect our child with PG adults with similar interests. Along the way we've met quite a few who are happy - all of them academics.
Of course there aren't large groups of prodigies to study because they are rare. The book I found most helpful is by Miraca Gross:
http://www.amazon.com/Exceptionally-Gifted-Children-Miraca-Gross/dp/0415314917 The real takeaway message I got from this book is that outcomes are not good when prodigious children's academic needs are not met.
If you want an anecodotal example, one of the children in the book is Terence Tao. He went on to have a great career in math including winning the Field's Medal (equivalent of the Nobel for math).
http://en.wikipedia.org/wiki/Terence_TaoMore generally there is quite a bit of research on grade skipping and acceleration.
http://www.accelerationinstitute.org/nation_deceived/ http://www.hoagiesgifted.org/acceleration.htm http://www.hoagiesgifted.org/grade_skipped.htm 
