I've only lived in the DC area for 6 mo. or so, but I've been to the Borders in Silver Spring, North Bethesda, Bethesda, and downtown and thought they were horrible, at least on price and probably on selection too. The B&N near Metro Center, on the other hand, had a much better selection when I went there for the first time last weekend. I found at least 4 books I wanted - however, I buy everything from Amazon (lower prices, or used books) and put them all on my wish list there.
It's been almost six months since borders filed for bankruptcy, and they were having cash flow problems before that. Many suppliers have been insisting on cash terms, which must have put a serious dent in their stocks. I was at a borders last week looking for a brand new Stross hardcover that I was willing to pay full price for but they didn't have it. An employee said they wouldn't be getting it, yet they definitely would have in years past.