Many people seem to switch to the parochial schools for middle school and then it is either Science and Tech at Roosevelt or one of the Catholic high schools. There are a handful of faculty offspring from this area attending the various "big name" privates as well - Cathedral schools, Holton, GDS, all of the Catholic high schools, come to mind as schools that we know kids at who have UMD affiliated parents.
Here's a link to the last "news" I've seen on the charter:
http://vpaf.umd.edu/newsletters/spring2012/Spring2012CommunityeNews.pdf
The word on the street with people we know was initial excitement which has turned into skepticism and disappointment at the few proposed details that have been released so far. I know someone who was consulted early in the process who is Education faculty. From the sounds of it, their recommendations were not heeded and things took a very different direction from the lab school model that was being advocated for by faculty members.
My concerns: socialization and community are important aspects of middle school and high school. While I want a rigorous academic environment for my child, I don't want it to come at the expense of having a collaborative learning environment and a school that has a strong sense of community. And also where are they putting the school?