This morning Twitter announced it's swapping out two board members for new faces. In the filing, it revealed that Peter Currie and Peter Chernin will step down after the annual meeting, to be replaced by Pepsi exec Hugh Johnston and UK entrepreneur Martha Lane Fox. Most notable about these additions is that in Fox, the board will have a director who is a prolific tweeter with over seventeen thousand posts on her account, while Hugh has... 2 (both posted today).