The full schedule can be found here, but a few notable things to point out.
First, D.C. United will be playing an unbalanced schedule this season, with the debut of MLS' 19th club -- the expansion Montreal Impact -- putting paid to last season's 34-game, home-and-home scheduling format. So this season, United will play 25 of their 34 games against Eastern Conference foes. As part of this arrangement, United will play two home games against Columbus, Montreal, New England, and New York, while the Black-and-Red will make two visits to Toronto, Philadelphia, and Houston.
Also, D.C. United will make at least twelve appearances on national TV. Five of those appearances will be on either NBC or NBC Sports Network (the network formerly known as Versus), which acquired the rights to some MLS broadcasts from FOX Soccer Channel for this year. The games on NBC Sports Network are: March 30 vs. FC Dallas, May 12 at Houston, August 19 vs. Philadelphia, and the season-ender October 27 at Chicago. The June 24 match at New York will air on NBC.
In addition, two further matches will air on ESPN2: the April 22 home match against New York and the September 22 road match at Philadelphia. Five other matches will air on Spanish-language channel Galavision: March 18 at Los Angeles Galaxy, June 16 at Philadelphia, July 15 at Houston, August 29 at New York, and September 23 at Chivas USA.