Late to the party on this but I recently ditched both my 26ers for 29ers. I had demos and borrowed a variety of bikes, both 29 and 650b before I made the decision, I tried both wheel sizes of Trance, a couple of Santa Cruz and Orange fives in every flavour.
Now just to qualify this I will state that I am not a racer of any sort, far too much of a pie enthusiast for that.
I was initially concerned about the talk of 29 bikes being harder to turn and much less agile than the smaller wheel sizes, I have found that this is true in varying degrees, but I have also found that it does not matter in the slightest.
The reason it does not matter is that what you lose in agility you gain in increased grip and stabilty, your riding style has to adapt, but once it does you learn that you can carry more speed in corners, and hold lines that would have had you weaving the bike around on a 26 inch wheel.
Obviously this is subjective, but I have found that I can ride longer without geting tired and that I am recording PBs on strava without really trying for them, probably down to being able to float over rooty and rocky sections rather than weaving around trying for the smoothest line.