John Farrell has confirmed on MLB Network Radio what we've been expecting: Joel Hanrahan has been activated, rejoining the team in Toronto. That doesn't, however, mean he's the closer, as Farrell has indicated (as relayed by Evan Drellich) that Andrew Bailey is likely to keep the job even after Hanrahan's return.
This seems like the best of both worlds for the Red Sox. However much of a question Joel Hanrahan is, Daniel Bard was a bigger one, so it's not like they lost much to get Hanrahan back on the roster. But for now, Andrew Bailey will keep his share of the important innings.
Where things could get dangerous is if Junichi Tazawa or Koji Uehara get pushed out of innings they otherwise would be pitching. Given the performances of each so far this year, however, that doesn't seem terribly likely either. If John Farrell's problem, then, is finding opportunities for Hanrahan to pitch, well, that's a good problem to have. Given how much they've been forced to use the veteran Uehara, it shouldn't be that big of one either.