Edmodo is fun because it is set up like Facebook with a newsfeed for students. Students like it because it feels like something they are used to-Facebook- but it actually is a way to give them lesson information and important handouts from classes. I also like that students get notifications for things that I post. There is also a messaging capability so that students can query teachers regarding classroom content. Lastly, I like that I am able to approve students' comments prior to their posting.
The issue is that there is no way to organize the information that teachers post so that student can find it in an easy and logical way. I would recommend that Edmodo find a way to organize teacher posts. I also dislike that Edmodo doesn't have a gradebook for teachers to use for grading student assignments on Edmodo.
I would say that it is convenient to use if you plan on not overly relying on this to disseminate information to students.
I am not a business person, so I don't think that this question is applicable to me.