I already have a 29er. It's called a cyclocross bike.
A while back I was considering getting a fisher 29er. Finally got to test ride one and found that I take a 17.5" Unfortunately, it almost castrated me, given the atrocious standover. The trails by me are fairly choppy and tight so I just wouldn't want to take a big wheeled bike out on them....I'm already struggling as it is with my crappy abilities and lack of fitness. There are a lot of variables in choosing a bike, of course, but I have to admit that the constant shoving of 29ers down my gullet in every publication I pick up is starting to piss me off. They just aren't for everyone, no matter how many times the industry shouts about it. Nice one Ed.