I lose respect for any company that badmouths other companies and their fans, and any company that doesn't respect its own fans as gamers.
I've regained much lost respect for Sony, who said a lot of really messed up stuff about the competition last gen. Since then they've been super cool about everything and have put a ton of focus on pleasing and empowering gamers.
Microsoft went down to about 0% in the respect department when the president himself basically called all Nintendo gamers babies who should be embarrassed to go out in public, and with all that early-gen craziness they sent out the message: "Gamers don't matter, and we control every aspect of your entertainment, and that's final." Since then they've been slowly regaining that respect, but it's a long road.
Nintendo has always been cool with me--easily the coolest of the bunch in this regard--but their stubbornness and refusal to actually do what the fans want is making my opinion slip a bit south. Then with Reggie saying all this rude jazz recently, they're getting into territory I never thought they would.