Maker Forums Discourse is back. It is likely to be somewhat slow and occasionally to show the maintenance page over the next few hours, due to the underlying site maintenance.
If you see the maintenance page, just wait. It will retry occasionally until it gets through, and should preserve where you were when the page goes away.
If you have questions, you can reply here, or in the Maker Forums Discourse thread about the outage here:
Microblogging for Makers. Part of the Maker Forums community.