She hasn't so far, but we don't know if Steven Moffat is planning to do something with her or not. One big question would be: if she does come back, will she be played by the same actress? Because the original actress (Georgia Moffett) has since then gone and had a baby, and I don't know if she'd be available... Of course, since the character can almost certainly regenerate, she's presumably bouncing around somewhere in the universe... Unless of course, she got unwritten, with Amy not having rewritten her. Which would be sad. But seeing as a lot of things Amy isn't' consciously aware of were "rewritten" into existence, there's still an excuse to use her, should the writers want to.
I do hope they bring her back, though unless they bring her back just to kill her off, she'd almost have to be a recurring character if not an outright Companion on the TARDIS, because the Doctor has been rather lonely lately, and I don't see him giving up on one of the few Time Lords/Ladies left alive; hell, he didn't even give up on the Master after learning he was alive after Gallifrey's timelocking, so I REALLY doubt he'd give up on Jenny after finding her alive.
It would be interesting from a dramatic standpoint,so I'm guessing the only things keeping them from doing it are along the lines of "wouldn't work with the overall Series plot", "actress not available (though as I point out, that could be worked around)" or "Russell T. Davies owned the character so they'd have to get extra permission" (<--- they have to do this with Terry Nation's estate whenever they want to use Daleks, so I imagine whomever wrote/produced that episode would have to be talked to about it; it's a very different situation with River Song, who originally appeared in an episode written by the now-current showrunner)