If you are logged in, you should be able to read however it is also possible that there may be issues loading the forum.
If you are not logged in, you will see a message that the orum is in maintenance.
The expectation is that this will be minimal... and will be back up (ideally 10 - 15 minutes though may be longer).
--
Update - Appears to have completed smoothy so forum has resumed
Christopher / Admin
