The problem with a market driven approach is that it's hard to convince people to get in to 'glorified bookkeeping' or other stuff like that. Industry applications typically are not sexy but they're a fantastic way to make money because businesses don't have a problem to pay for things that will save them money, time or both.
If you're in it for the money go for b2b any time over b2c, b2c is sexy, everybody will write about you if you score but the fact is you most likely won't.