Besides Go Mama Go (fun and eclectic decorative stuff with an Asian tilt), there's also Home Rule which is the pioneer of this block of furniture/home decoration stores. They're both located on 14th ST between S and T. In addition, there's Vastu and Muleh on the same block. All are worth a visit. Around the corner on U, there's Urban Essentials which is fascinating too. Further down 14th (closer to Logan Circle), there's Reincarnations and Maison 14. Between these 7 stores, I would say you would encounter much of the shopaholics amongst us DC-ites

(especially on a nice day when strolling is encouraged).
I would definitely agree with Rice, Local 16 and Ben's Chilli Bowl and would like to add Kuna (U between 13th and 14th) with spectacular provincial Italian food in a tiny but charming and very personable setting. Don't miss Cafe Lovecake - the cakes there are to die for.
As a previous poster mentioned, Rouge is a distance away from the U St corridor (it's closer to Dupont Circle) but the bar is very hip. It is the pioneer of boutique hotels in DC which now include Helix, Madera (with a great restaurant) in the Dupont Circle area, and Monaco and the George closer to the downtown/Mall area. I wouldn't recommend staying along the U St corridor; better to stay near Dupont Circle which is a lovely (and lively) 20-min walk away.
The "New U" is definitely up-and-coming as evident by the large numbers of condominiums going up along U and 14th St (especially around the Metro subway station on 13th/U and the Whole Foods grocery store on 14th/P) and the slow-but-sure encroachment of Starbucks outlets (gentrification is only a Starbucks away!). It's well worth a detour from the usual National Mall/Georgetown/Dupont Circle tourist scene.