I am a heavy Google Reader user and while I was checking my feeds on my iPhone at the Verizon Wireless store (ironic) last night, I noticed that Google Reader began bugging out. Also, throughout the day, the "unread" count was higher then what was being actually shown as unread, earlier in the day.
Both issues resolved themselves after a few hours. I did survive without clean access to my RSS feeds for an hour or so. But I was not the only one to notice.
We have dozens threads at Google Groups, the largest Google Groups has most of the complaints.
Roger, the Google Reader Guide in the group, said:
As you've noticed, Reader experienced some temporary outages last night. We've been working through the night to fix the issues and all the major problems should now be resolved. There may still be some features not working properly, so please let us know if you notice anything else amiss as we continue to investigate.Thanks and sorry for the inconvenience.
The bulk of the messages came throughout the day. I believe it was all fixed by 9pm (EST) last night.
Forum discussion at Google Groups.