650b is the new fad. So lots of people who bought 29ers when they were the new fad (as opposed to those that just bought them cos they liked them) will be selling off their bikes and moving to 650b.
Heard that Giant have dropped all 29ers for 2015, even XC carbon hardtails! If that’s the case, I can imagine it might bite them in the arse soon enough. Plenty of people still like and want 29ers. And despite what the nay sayers say, they work for people of different sizes and they come in all shapes and flavours, not just XC race bikes.
I don’t think it will be all that long before 29″ wheels become the preserve of large and extra large trail bikes. For xc, where it’s all about going fast, I can’t imagine many people will switch to 650b unless the courses are really stop-start and technical.
Whilst in the long term, this is probably likely to happen. I think over the next couple of years, you’ll see the big companies hang their hat on a wheel size and keep on trying to sell it as a one size fits all solution. 26″ wheels still have their place, as do 29ers for definite. The industry that created all the different wheel sizes cos it wanted to sell you a new bike, wants to settle down on 650b as quickly as possible cos it means it’s easier for them to manage. Of course now they’ve created the wheelsizes and the market for them, there are now the customers too! So all 3 wheel sizes are going to be here for some time yet I think.