I do not think that there is a Facebook group for people accepted to Northeastern yet...but if you find one or somebody creates one, I would love to join!
NU was my top choice for several reasons: (a) Both of my sisters and my brother-in-law completed their bachelors (not SLP - my sisters both studied Mathematics and my brother-in-law studied Biology) at NU and loved the campus/experience/facilities. I visited the campus several times while my sisters were attending and really enjoyed it. I have heard great things about Northeastern's SLP facilities as well (will be checking them out myself on April 2nd). (b) I really, really love the work and research (like the iPrompt-U) that one of the NU SLP professors (Dr. Rupal Patel) is doing. You should watch her TED talk about synthetic voices if you get a chance - she is amazing! (here is a link to NU's SLP research projects page: http://www.cadlab.neu.edu/research.php) My two major areas of interest are medical SLP and second-language learner SLP, and I think that NU will give me fantastic opportunities to explore both. I spoke with a former NU SLP grad student who told me that, in her experience, NU students often get selected for competitive medical clinical placements in the Boston area instead of students from the other 3 Boston programs - which is also something that Northeastern itself advertises (this may have something to do with Northeastern's phenomenal school-wide co-op program, which I imagine fosters some pretty solid and mutually beneficial relationships between NU and the Boston hospitals in general. I also suspect that MGH students probably get a lot of great MGH clinical placements, which means that NU students are only having to compete with BU and Emerson students for some of the other spots at other hospitals).
My third reason is probably only applicable to my specific situation: Of all 6 of the Massachusetts SLP grad programs, I will get the most 'bang-for-my-buck' so to speak at NU. All of my tuition will be paid for with the GI Bill and NU's Yellow Ribbon Program, with a great housing stipend ($3100 a month). I had been considering applying to MGH's and BU's SLP programs, but I may have ended up having to pay a little bit out-of-pocket for some of MGH's pre-req courses, and because I knew I was applying to BU's MA in Modern Foreign Language Education-Arabic program, I didn't want to apply to their SLP program as well for fear of being accepted to neither, should the programs discover I had applied to both. Emerson is obviously also a fantastic school with a great SLP program - but I have heard that it is more geared toward school-based SLP than medical SLP so I wasn't particularly interested. I also applied to Worcester State University (where I did my post-bacc) and have yet to hear back, but I know that I will be declining their offer should they admit me because Northeastern's program will be a much better fit for me (plus the monthly housing stipend for attending Worcester's program is only $1900 a month).
I hope that any of this information was helpful...after I go tour the facilities in April I may be able to provide a little more insight!