Greetings!
I can help you tweak your thesis a little. However, I'm not really sure what you meant by the second sentence. I'm not sure how having more friends is a bad thing...?
If I were writing it, I might say "Myspace is about getting more people to create a Myspace page, and that is a good thing for the creators of the social networking site. However, there are disadvantages to the users of the site which may not be evident: putting too much information on your Myspace page can be dangerous."
I hope this helps!
Thanks,
Sarah, EssayForum.com
Sarah, EssayForum.com