I emailed Newsgator this morning when I noticed that their site was down. I just had this response:

"Dan,

NewsGator Online has been experiencing intermittent system problems (Case 57879), starting late last night. We are working hard to correct this issue and expect the problem to be solved within the hour."

So now we know. I wish them all the best in getting this sorted – it's never easy trying to get a knackered system back online, let alone one with as many rss-addicted junkies users as Newsgator has.