I don't see any good reason for raising rates other than Greenspan needs a reason for being. He admitted (after the fact) it was raising rates w/o real inflation that started the recession of 2001.
They should stay flat for a while IMHO, but Greenspan wouldn't feel like he has a purpose if he did that.
The dollar has been weakening for months. If rates aren't raised it will continue to lose value. Great if you loved the inflationary Carter years, I suppose. If anything Greenspan has been guilty of adding fuel to financial bubbles for several years with his loose credit policy. The housing/mortgage bubble will be next to explode, a situation made far worse by too many years of cheap credit.