Something that happens in my personal newfeeds from time to time (using Opera as a reader/aggregator) has me very curious - mostly because I want to avoid doing it on any site I am involved with.
Several feeds that I appreciate very much, including really high profile businesses as well as others, sometimes start sending out the same old items with old dates included, day after day after day. How does this happen? Seems like it must be an easy error to make, whatever it is.
Before I went with Opera's integrated RSS reader, I used Amphetadesk and also saw this occasionally. I see rather regularly it on battellemedia and wired magazine (may be the same exact backend, now that I think of it!)
I know that the WebmasterWorld feed will issue a new item if we just edit a single letter, but I've never seen our feed keep looping through old news for a week the way these two can.