Why would it be an overreaction? The team is getting old and older still. May be time to let some folks go to free agency, trade a couple of guys who are aging, nab a couple prospects or whatever. Cano and Granderson are on the cusp of getting really expensive themselves while the Yankees publicly say they want to get closer to/under the salary cap.
I think it would be an overreaction to blow up a team that reached the ALCS and that had 95 wins despite having the most DL days in the league. Thankfully that's not their MO, despite the stupidity of most Yankees fans who think it's a total failure not to win a championship and that you have to "sign players that are good in the postseason". I doubt they'll make any crazy move based on what happened in the past week.
They should - and will - make changes at the margins, like letting Swisher go (for money/aging reasons rather than postseason performance), maybe trading Granderson or letting him go after next year (to save money for Cano). Soriano will likely opt out. They might try to trade A-Rod, but I doubt the small savings from that would make sense for the team. I would bet the core starting next season will be very similar. They'll probably try to bring Pettitte and/or Kuroda back (even with normal aging curves they should be pretty good). Pineda could be back by mid-2013 if he's healthy. It should be a 90+ win team.