For the non-geographically inclined...that's directly across from the Navy Yard Metro entrance on the same block as the current Bullpen.
According to JDLand.com, the atmosphere is expected to be very different from the current Bullpen, but is expected to be open the same hours. It is also expected to have a variety of German beers on tap. While this all may seem a bit excessive, it appears they may be adding this second establishment for a reason:
"At an ANC 6D ABC subcommittee meeting tonight, a Bullpen rep explained that Akridge, the owners of the entire block bounded by M, N, Half, and Van, has informed the Bullpen owners of plans to begin construction perhaps as early as October of this year on the southern end of the block, where Bullpen 1.0 is located. (There seems to have been some sort of "hint" that if the Bullpen wants to have a shot at a permanent home in the new ground-floor retail spaces that will be available when the block is completed, they need to expand to this additional area this year.) If Akridge's plans are unchanged from what went through the zoning process a few years ago, the southern end of the block would be a 300-unit residential building with ground-floor retail."
While I am usually the type to want to get directly to my seats as early as possible (love to see batting practice if I can), I have spent my fair share of afternoons at the Bullpen. It's a great establishment and I think it's one of the best thing Nats Park has going for it. Neither Nationals Park nor Nationals Baseball have very much culture right now, we're a very new franchise without much history...and let's face it...we live in a city that's pretty much a melting pot of out-of-towners, which means unlike cities like Pittsburgh we don't have a common bond that many other team's fans can claim.
The Bullpen however serves a great place for Nationals fans to come together and enjoy a good time before watching some baseball. Here's hoping the second iteration provides just as much character.