Suggest you go to "yahoo groups" and sign up for the list-servs of the various neighborhoods. Also check crime stats here, but you need the zip codes:
News in 20009 | EveryBlock Washington, DC
This one is linked right now to Col Hts plus Adams Morgan and Mt Pleasant, since all have the same zip, 20009.
Remind me what your budget is. And do check whether GTU has a housing board! I know AU does...
Also if you're moving here soon, you probably could rent something for the summer and use that as a base to go exploring.