Lately it's looked like the economy is doing well in the neighborhood. It never really slumped too much, at least as much as the rest of the country, but housing rental and sales were low, and some folks cited the economy as a reason for not opening stores (like Ellwood Thompson's) or for closing them.
However, the City Paper recently posted a piece where Columbia Heights was the "hottest" residential real estate neighborhood according to Redfin, a real estate website. And just this month there are a number of new retail and food spots opening up, like Alero coming to the Rumbero's space, Pica Taco at 14th and Florida, and Z-Burger. The Columbia Heights Community Marketplace is opening soon too, which should bring more people to the neighborhood too.
It might be too early to tell, but it looks good to me. I'd like for there to be more interesting retail, especially of the non-fast food kind. Fast food is tasty, but too much is never a good thing -- either for your stomach or for your neighborhood.