If you have seen The Avengers (which is also known as The Avengers Assemble in the UK, so as to not confuse it with another film of the same name), you are probably already aware of what happened to Agent Coulson at the end of the film: after standing up to Loki just before the events of the Battle of New York, it appeared that Agent Colson was killed by Loki. But now that the sow "Agents of SHIELD" has premiered, we now know that Coulson did not die from his wounds (or at least, he did not stay dead).
Now that Coulson has been resurrected and put in charge of his own team of SHIELD agents, we know for certain that he is back on the job being the amazing agent that he is (the one who so often was able to get things done). We also know (from a cameo by Samuel L. Jackson) that Nick Fury is very much aware of Coulson's resurrection, and the fact that he is back out in the field, doing work for SHIELD. We can probably assume that since Fury is aware that Coulson is working again, and that he is back working as Coulson's supervisor, that he probably reserves the right to send Coulson out on missions.
During Phase 1 of the Avengers films, Coulson seemed to be Fury's favorite agent . . . the one that he was most likely to send out into the field when things got a bit strange, so that they could be taken care of. It not only attests to the fact that Coulson can get things done, but also that Fury trust him to get those very things done.
So, if we know for sure that Fury is working at least to some extent with Coulson again (despite Coulson having his own team now), would it really be likely that Fury would not continue to use him in the future? Even if he's working with his own team while on "Agents of SHIELD," that does not mean that Fury would not be able to pull him aside and have him look into something that looked particularly strange (especially when it might involve any of the Angers in some capacity).
And it does not hurt his chances any that he is so popular with the fans. If you are popular enough that you are brought back from the dead so that you can become the lead character in a television spin-off of the films that you were the chief Easter Egg in . . . there has got to be a good chance that your popularity is going to be capitalized on as much as possible.