I'm currently using feed43 which generates feeds limited to 10 items. For some feed43 feeds in newsblur I get a history of 200+ items and for some others I only get a history of 10. Could you explain me why?
By the way NewsBlur is a great product and I'm very happy to pay for it!
Most likely Feed43 only ever makes one feed for any given source. So if two people make a feed for the same thing they both get the same feed URL.
Then we have newsblur which takes feeds given by users and contentiously fetch these feeds server side and save each item to a database since very few feeds contain more than the most recent items.
So for the feeds you only get a history of 10 items you are the first person to add that feed to Newsblur, and for the ones where you get a longer history someone else has already added that feed to Newsblur.