Stop, Collaborate, And Listen!! (borrowed from Vanilla Ice!)

Since I've learned about awesome, new collaborating sites this summer, I would like to start using one this next school year with my 8th grade courses.  I'm a little worried about how to start this out, and would LOVE any feedback! Once I get it off on the right foot, I feel it will be absolutely beneficial for everyone involved in my classroom (the students, parents, me etc).

Currently, however, I've been researching a couple different options. What I'm looking for in a collaborating site, is something on which I can post assignments and announcements, but also where students can post discussion questions and responses, or find out what we did in class that day/get assignments if they were absent.  I would also like to possible have the site host a book discussion at some point.

So, here's where I'm at.  Since I'm going to be teaching primarily reading/English blocks, I would like the students to have their own blog, as more of a journal for reading responses. I love Edmodo, it seems very user friendly and a nice layout for middle school students. But, I've recently come across Collaborize Classroom (during PD investigations on live.classroom20.com).  Collaborize Classroom has similar features as Edmodo, but it allows the teacher to have the option to post four different question types and has a cool results tab, saving the teacher some grading time. 

Does anyone have any experience using Collaborize Classroom...it seems like a new program? I would love some feedback about what features you look for when beginning this sort of collaborating site. 

So, I guess my 3rd project is a work in progress...I hope everyone understands that I have ideas in mind and I will be starting up a site this fall...I'm just looking for a little feedback on both programs!