Mayor Bloomberg has only two years left in his mayoralty, and in that time he has got to get a lot of big things done. As the economy is dipping, he’s faced with flagging momentum on many of the enormous new development projects he’s encouraged. And many of the other elements of his green-friendly PlaNYC initiative won’t go into effect for another 30 years. (Let’s also not forget his failed attempts to get a stadium on the West Side and the Olympics in the five boroughs.) So he must have been extremely pleased yesterday to see that one of his biggest efforts to make a permanent physical change of the face of the city took a long step forward. The City Council narrowly endorsed his congestion-pricing plan, thereby sending the initiative to Albany where Senate Majority Leader Joe Bruno is believed to have the power to pass it (Assembly honcho Shelly Silver, well, he’s doing what he does best — digging in his heels). If it goes through, we’ll be seeing an $8 commuter fee for cars going into the city during the day, a $21 fee for trucks, and a bundle of extra money for bus and subway lines. But more important for Bloomberg, we’ll be seeing a cleaner, quieter, more breathable, and less-trafficked cityscape. As far as legacies go, Bloomberg probably realizes that the absence of all that mess might be even more visible than the presence of a half-dozen skyscraper projects.