DAVE and BWW are only partially competitors. They have different foci and significantly non-overlapping menus and clientele, and share mindspace in the overlap. That is, very few people are going to BWW who aren't also going to DAVE.
Restaurant trade was picking up the past few months. Tons of openings of all kinds of sit-down places in my area just since Thanksgiving. Then the Arab world got restless and oil prices have spiked and it's looking like a volatile spring is ahead for everyone.
DAVE depends on expansion to grow. The closures in the NE were to blame for missing profit numbers on good revs this Q. If DAVE had been able to grow through '10 those closures would have been offset by openings and would have been a smaller hit to the overall value of the company.
If the OPEC types stop blowing up their populations, gas prices come down, and margins can be improved predictably, I expect expansion to resume in a big way. DAVE is a very popular concept almost everywhere it goes.