There is now a new kosher place in DC called Eli's. It's at the corner of 20th and N St NW, about one block south of DuPont Circle. It's owned by the owners of Siena's.
We had a burger and a steak. The burger was great, the steak wasn't cooked right. Service was spotty, but we didn't hold it against them as we attribute that to the fact that they were in their first week or so.
The prices were great -- our entire meal, plus tax and tip, was less than $48 (i.e., less than buffalo steak at the Red Heifer, which is closing tomorrow). The most expensive item on the menu was $24.
They don't serve alcohol -- yet. The waitress said they were still working on getting a liquor license.
The ambience was very nice - probably a bit higher than your average DuPont circle cafe.
We have high hopes for the place, and am planning on going back soon, possibly tomorrow night.