well Microsoft pissed off Valve in alot of ways with making them charge for L4D2"s The Passing and such. Valve wanted it free, Microsoft is to greedy and said no. I believe this works in Valve's favor as a "screw you Microsoft" type thing.
As he stated on the number of updates. Sony would probably have approved well over 5 updates. Even if Sony only accepted 15 updates for L4D2, Valve would have pointed out that Sony is more dev friendly.
Also you guys have no idea what Gabe's past looks like for past technologies. When dual-core processors were released he pissed and moaned that he would never develop for them because the extra core is useless. As of last year all of Valve's dev PCs are running quad-core Intels. See where things went? Gabe is a brilliant developer who is just lazy to learn new tech, once he learns it he loves the increased freedom. I wouldn't doubt during his "I hate the PS3" campaigns he had a PS3 dev kit on his own desk learning how to code the Cell.
