User blog comment:Blood Reaper/Todd Howard Hinting at Future DLC's and Patches/@comment-67.234.62.46-20120302193843/@comment-88.22.153.23-20120307000048

"Would also be interesting if they made a perk-buy back thing, where you could choose to remove already selected perks and use them for something else. More or less wishful thinking at this point though XD"

You can do that with a little help of the console :)