Not set up profile just go to message board
Is there a way for a new user, once logged in just go to the message board to begin posting. Right now, once a user logs in her or she is taken to set up their profile and this is confusing users.
This kind of redirection only exists when user register and login first time in case the "Registration with email confirmation" option is disabled in Forums > Settings > Features admin page.
In any case as Sofy said you can set custom redirection pages for log / register actions in Dashboard > Forums > Settings > Members admin page: