2010 has FIT damper. Shaves a very small amount of weight, but is supposed to have much improved feel - I have one coming to me this week. Haven't ridden the 2009 to say - the 15QR is definitely an improvement - it will be much stiffer, comparable to 20mm, just a different standard (the people that actually use it instead of bashing on e-rides like it a lot... for my 120lbs, i went with the standard dropouts).