Alex Speier has a nice look at Jacoby Ellsbury's career so far. What Alex doesn't do is suggest what the Red Sox do with their enigmatic centerfielder.
Here's what I'd do.
First thing to know is that the Red Sox have control over Jacoby Ellsbury for one more season (2013) and that Ellsbury's agent is Scott Boras. You put those two things together and it is clear that there will be no long-term deal cut this offseason. Ellsbury will use the 2013 season as proof as his worth as a free agent. I think that's great news for the Red Sox.
Let Ellsbury put up big numbers in his walk year. If he can do something like hit 25 HR while stealing 30+ bases then that will go a long way towards getting the Red Sox back to the playoffs. The season will also allow Jackie Bradley Jr. to get more minor league seasoning before a potential September call-up. Next year will go a long way to see if Bradley can succeed Ellsbury in center if Ellsbury walks or proves too expensive.
If the Red Sox are out of the playoff hunt by the trade deadline - then the Red Sox may just trade Ellsbury (you can no longer assume the Red Sox are a playoff contending team). If they are in the hunt - a healthy Ellsbury will be a powerful weapon. Either way Red Sox fans should enjoy Ellsbury wile they can because he won't be around in 2014.