That's the general meaning for timeout. It just means that the data that was being accessed wasn't returned within the time limit. "Normal" limits are often 60 seconds, but it can really be anything. Check with Feedburner to see if there is any way to change the timeout settings. Every once in a while, my blog will time out when my Google Gadget attempts to grab the feed, so it may just be a DH problem.
How do you like feedburner?
Check out Gordaen's Knowledge, the blog, and the MR2 page.