IF you're are logged in and CAN'T find the BBLog icon on Battlelog like on this Picture:
http://getbblog.com/img/screens/interface.jpg?v2
(top left corner, with "BBLOG Options", next to "home" and "multiplayer")
Than please go to this Topic and follow introductions:
http://getbblog.com/viewtopic.php?f=23&t=529
If nothing changed and/or BBLog is still not visible/not working, contact us again in this board, and follow the introductions from Nano (post Screenshot). Hope we could and can help you =)