Thusgrook did a test a while back with all the speeds of XMS he could get his hands on (3000, 3200, LL, etc) and they all did very close to the same speed, and some of the lower-rated modules actually did better. It seems like all the modules that Corsair uses go into one big pot, and Corsair just puts on different heat-spreaders and calls it a day. With these new loose timings, I can only guess it is because yeilds on DDR aren't getting any better.
I don't know about you all, but I am ready for DDR II to get here.