Goldoni's (the Oestria, not the Teatro) on 20th Street bet. L & M, has been replaced with a Tex/Mex place called Vida.
The restaurant is still attractive, there is a pretty big bar, they have wonderful outdoor seating in the plaza area, and the beer is cold.
Other than that, the menu offers and the kitchen delivers standard prices and standard fare ...quesadillas, tortilla soup, tacos, burritos, enchiladas, burritos, etc. A recent lunch confirms that the food is fine, but at least one full notch below Cactus Cantina or Rio Grande. I should note that the menu had a third page of more orginal and expensive entrees, (fish, chicken and meats with sauces) that we did not try.
I'm not expert on the restaurant business, but I'd be willing to venture that you have to serve a lot of refried beans to pay the rent in that location.