The game is multi platform.
Your B.net account has a linked PSN account. This leads me to believe you will be playing on a PlayStation.
I will be playing on Xbox. Even if I were to follow you on B.net, I definitely wouldn't be playing with you in game. I couldn't.
There is no correlation to followers on B.net and your fireteam in Destiny.
Followers are irrelevant to the game to our knowledge. It's a forum based feature to let you keep tabs on the people you like as well as spot them on the forums. That's it. (Aside from preserving the E-peen of some of our older members once titles were lost in the B.next Update.)