It's all back-end stuff, but today we made some significant database changes to increase performance and capacity. This meant FeedDigest had to go off the air for two small periods today, so we apologize for the inconvenience. We try not to ever take it down, but the benefits from these changes were too big to put off.
We also had to stop our crawlers for about six hours, as we were more interested in digests being served reliably, than keeping the digests up to date, and we had to prioritize. The crawlers are now back up and running and busy running through the backlog. The database updates mean that crawls should be a lot faster, so we may (and there's no promises yet!) let you recrawl your feeds more than once every thirty minutes.. (indeed, we already have it running at every twenty minutes on the backend for 'test' purposes, but may lower this further..)
So, it's all go here, but the changes remain on the backend for now. Perhaps (finally?) we can roll out the more exciting features if this database upgrade truly gives us the stability we need to grow further and to ensure we can handle hundreds of new users day by day. Thanks for your support; we truly appreciate it.
Added: Peter Cooper has posted information on his blog about the changes made today.