The Red Sox have come out in favor of a salary cap of sorts, although the lack of details available - particularly whether or not the program would be a standard salary cap, a payroll zone (where there would be both minimums and maximums on team salary), or something else entirely - makes me wonder about the intention of this announcement.
On the one hand, I can see why the Red Sox would want a cap: they have a reputation for winning and for a devoted fanbase, making them more likely to win the favor of players on the free agent market and giving Boston a better pick of available talent. Coupling that attractiveness with a cap - and the dollars to spend up to that salary limit - eliminates the possibility of losing a player to a higher salary bid, increasing the likelihood that a Mark Teixeira ends up making Fenway his home.
On the other hand, this announcement could just be a ploy: get in a cheap shot at the Yankees, throw in another - with the payroll zone comment - at the Rays, make the ownertship look like it cares for the plight of the common man without having to worry that a cap - which would have to meet the approval of the unsympathetic players union - would become a reality. Sounds like a win for the Red Sox no matter what the intentions.