Councilman Tony Avella (D-Queens) will be formally announcing his bid to replace Mayor Bloomberg this Sunday. Theories about likely candidates abound (e.g. Councilman John Liu, Rep. Anthony Weiner, Council Speaker Christine Quinn, City Comptroller Bill Thompson, and NYPD Commissioner Ray Kelly), but Avella is jumping to the head of the line by explicitly announcing his desire to be Mayor this Sunday at 1 p.m. on the steps of City Hall. Avella is the chairman of......