The last poll, as you may know, was asking to the Wikia Community what was it's favourite Call of Duty developer. While for the first days Treyarch was leading on the poll, but then after the PS3 patch in Call of Duty: Modern Warfare 2 made the poll shift, giving 46% of the votes to Infinity Ward, beating Treyarch.
Even though strange, the opinions changed as well; it had been stated before that the MW2 was potencially the worst game of the franchise. Now, seems that it surpasses Black Ops principally because of the overpowered and over-used RC-XD's, making the severe flaws from MW2 forgiven, making the overall ranking given by the community of the game boost as one of the best. The community that at the start of the Black Ops era seemed pleased because TreyArch gave the balanced game that MW2 didn't had, now they go back to the un-balanced MW2.
If you want my opinion, I made my vote to Treyarch. They deserved it, they made the balanced game I wanted and now I can "pwn noobs" without getting a Grenade launcher with Danger Close or an UMP45 with Stopping Power. If you prefer MW2, no problem, but don't forget that Treyarch at least struggled to get a balanced game done, without boosting or cheating, that you and the community asked back last year.