Way back in the day the City of Heroes (Prima's Official Strategy Guide) said it was go to be a option and was going to be a massive in game under taking but the powers that be have said nooo's and it never saw the light of day and from the resent Q&A will never at this date see it either.
But if it did would I use it...Sure, I have several level 50 toons that just dont play the same and some that frankly suck now. Rerolling is the only option but its still not the same. Ive done it like so many of us have but how many clones of the same toon do I have to make just because a new powerset came out that may or may not be better then what I had on that toon. But since it's NEVER going to happen I'll keep rerolling rolling rolling.