This rumor has been floating around for a while, but reared its head again earlier this week when New York Mets brass expressed interest in bringing a second MLS team to the New York area, thus creating a natural rivalry with the New York Red Bulls.
MLS tried this inter-city rivalry out west in Los Angeles when it admitted Chivas USA into the league. It's been a mixed bag, with Chivas attendance dipping and a second class citizen status developing at the Home Depot Center. (It's doubtful any new NYC team would be an extension of an existing club.)
Right now the Red Bulls play out a nearly non-existent life in the shadow of Manhattan, with next to no media coverage from the plethora of Big Apple mainstream outlets.
The advantage for this possible Mets entry into MLS is that first off, it would have to have its own stadium plans in place. Second, the Mets own their own sports network in New York -- SNY -- which would give the team coverage by default.
Overall, it been odd that MLS has never taken root in New York and another team probably won't change that. There would seems to plenty of other worthy expansion city candidates -- Portland, St. Louis, Cleveland -- before New York gets another shot. Yet if the funding is there for a stadium, it has to be considered.