I've just migrated hosts for my website and managed to spam at least one aggregator in the process. (I think this is because git does not preserve timestamp metadata for blobs but I haven't investigated properly yet). Apologies to those affected. Luckily, I have my feed configured to only show the most recent 5 items, so the impact was quite small.

I think this should be the default for applications that generate feeds for precicely this reason: It is for blosxom (#373570) and pyblosxom (#373658), and ikiwiki specifies a limit, at least.

Asides from feeds, I think blog web pages that display an enormous number of posts on the front page (or inside category pages) are demonstrating some pretty bad usability. I thought that Jakob Nielsen may have included this in his Weblog Usability: The Top Ten Design Mistakes, but he didn't. Thomas Watson writes we have celebrated with finally scrapping our blog archive. Instead we are now just showing the latest 50 articles on the front page, followed by a link to the previous 50., which pretty much the opposite of what I'd advise. The point he makes, though, is that the alternative (an ever-expanding "archive", accessed by calendar) is bad form, too. That is one of the points in Nielsen's list.

Jonathan Boutelle describes an interesting compromise which he calls the "Mullet style" - a short list of full posts followed by a list of older posts, containing only their titles and date.