Smashwords occasionally has downtime problems and it's looking like this morning could be one of them. I only see a little bit of Twitter traffic on it, but the problem seems to have started early this morning, US EDT.
Here's hoping it doesn't last as long as last time!
p.s. I found a service that reports when a website is down.
UPDATE: (1:15 pm, US EDT) Looks like it's back up. Hopefully, it will stay that way!