Right, but lately there have been quite a few dupes. I've noticed a lot with "?feed=" etc.

What about HN also storing the page title ? Upon submission, strip after "?" to check for dupe, in case of positive, check page titles to confirm.

Or just check, upon first submission, that the query string is irrelevant (fetch pages with and without), and strip it out if it is.

A bit slower, on submission, but that wouldn't be bad ;-)