Sean Wilentz is a history professor at Princeton University, and a hard-core lefty.  But his piece in Newsweek sharply challenges Barack's pretensions to being the candidate of change, and compares him to the most disastrous president in most living Americans' memory:

Obama's liberal alternative to the post-Bush GOP to date has much in common with Carter's post-Watergate liberalism. Rejecting "politics as usual," attacking "Washington" as the problem, promising to heal the breaches and hurts caused by partisan political polarization, pledging to break the grip that lobbyists and special interests hold over the national government, wearing his Christian faith on his sleeve as a key to his mind, heart and soul—in all of these ways, Obama resembles Jimmy Carter more than he does any other Democratic president in living memory.

Ooh.  True, and scary.