I was having problems the last 24 hours, but finally it's back up for me...go figure this would happen on the day I needed to download a newer version of routerboot.
I could not get to it when I needed to yesterday either. I could traceroute to it, get to the MT site, which appears to be on the same system, but couldn't get to http://www.routerboard.com. https://www.routerboard.com came up fine, but at the MT site, not the routerboard site.