Valve has had a, lets say questionable past with promises to fans. Way back in the day they were the leading front of the PC gaming industry. Nowadays they seem to have forgotten their heroic past of actually developing games and have secluded into the some what of a sole distributor for many AAA and indie titles. However, if there is anything Valve cares about, its money, and they will lose money if they mess up the Pyro update. Several members of the community have threatened to leave the game for good if they mess this up, and less players means less money. And Valve likes money. So maybe it will suck. But Valve will suffer if it does, and so that's why I believe they are doing everything in their power to make sure it goes over well.