I imagine it wouldn't be uncommon for someone to draft up a contract, or to be given one, and then come to Law.SE and ask "Does my contract look good?" or "What does this contract mean?"
How will we handle this? Will it be welcomed? Discouraged? It doesn't seem like a matter of opinion and it certainly falls in the domain of the law. That said, it also feels off-topic in the same reason source code review was for StackOverflow, which prompted the creation of CodeReview.SE. I can't imagine a LawReview.SE would be something reasonable unless this SE becomes wildly popular for some reason.