I can't tell you anything specific about Dulles (whenever visiting the DC area, including my recent post-11th trip, I fly Southwest into BWI), but based on other airports I can tell you a few general post-11th things:

The time you need is extremely dependent on various things. For example, at some times of day in some airports, due to descreased traffic, people with no checked baggage find they can get through in LESS time than before. The long lines that you see on TV seem to always be for baggage/ticketing. And those can vary a lot from one airline to another.

Furthermore, in general, the post-11th rushes can be very dependent on time of day, for various reasons. At LAX, several of us have compared early morning and versus early and late afternoon, and found carryon (X-ray) lines to be longest in early morning. (None of us comparing notes there have done midmorning since the 11th tho.) What seems to happen is that at certain times of day (including overnight ) they understaff those caryon screening stations, and then when a rush hour hits (like early morning short-hop commuting flight time) they may not be ready enough. By midmorning I would guess that the rush of business commuters would be over and there's no rush of midday travelers expected so it should be a bit better.

But since none of us comparing notes about LAX have checked baggage since the 11th, I can't even tell you from experience how fast those baggage/ticketing lines move at a particular airline in any other airport, let alone Dulles, sorry. I've heard conflicting stories on TV, with some people who were in really long lines wrapping all around like the worst lines at Disney World later say they got through it all in just 30 minutes, and others on other days (and quite likely other times of day and at other airlines) saying it took many hours.