Oh yes this debate will never die. I try to stay out of it as much as possible because it is what it is. Ride what makes you happy and ride what gets YOU down the trail the best! I personally ride a 26er and probably will never drink the kool-aid and join the 29er craze. I have ridden a couple, they have their pros and cons but I don't feel they are worth the money yet. They haven't proven themselves to me but I will remain optimistic as they continue to improve year after year as they move from rigid to hardtail to full suspension XC and now into the 120-140mm trail bike scene and some are pushing into the All-m scene and rumors have it soon into the freeride, dj and dh scene? Slightly skeptical of this but who knows. Here are some good articles to fuel the fire.
First is a write up by Lee McCormack and his take on his 29er experience: STUMPJUMPER COMP 29 TEST
The second is from PinkBike.com and the more aggressive side of the sports take on 29ers- the write up is good, I like the guy from Norco better, he gives more facts and straight talk the guy from Niner is just pushing a big advert- but I think that happens a lot in the 29er market- big companies just pushing beliefs with out sustainable facts, again we will see : Click Here
Who knows what will happen but my guess there will always be both now and it will be a consumer choice!
here's a pic of what a DH 29er might look like....