Exactly. Take a tour of the SF and Mountain View coffee-shops which offer free wifi with a laptop to sniff traffic. Isn't there a not-negligeable chance you might recolt some HN cookies from "interesting" accounts? Once you get them, it's just a matter of imagination before causing some harm.
HN is not the small and unfamous news site it was 2 years ago anymore.
And not just interesting like a high-profile person, but interesting like a YC founder who is a moderator. It's possible that PG has instructed mods not to log in over public connections, but I bet they occasionally do it.
And how much damage could a hacked moderator account do to the site? This whole conversation seems like a symptom of taking this site way too seriously. The community is very valuable and even important. The site is just an artifact of it.
As evidence for my point of view (and, you can say "you're welcome" if my brinkmanship with this sentence is paid off by Graham promptly enabling SSL, which he could easily do in the process of fixing the far-more-important bug of this site not being served through a front-end proxy), note that next week SSL will in all likelihood not have SSL enabled. That request --- provide SSL --- has been outstanding forever. Does Graham also share my cavalier attitude towards the site?
But remember that this is also the YC application system. A lot of alumni help read apps, probably just by getting a permission added to their account. So a lucky firesheep-er can probably read every application to YC. And mess up people's applications (if they get the account of an applicant before the deadline). And may reject people/delete apps if they were to get, say, pg's or harj's account.
And possibly other stuff. I don't know what all YC uses it for, but I get the impression that they continue to use it for various things (signing up for office hours?), some of which may be sensitive, once teams are accepted.
I addressed this point in another comment. Briefly: my advice regarding that fact would not be to improve HN's security; it would be to get the YC functionality off HN, stat. HN is way more a target than YC's stuff ever will be. Most of the people who will take a run at this site don't even know what YC is.
Ok, that would work too. But I'd guess that there's significant barriers to doing that (ie. it would take a lot of work to make it happen).
Plus it's never optimal, even for a bs written-in-a-weekend app, to send passwords in the clear, given how many people use the same password on multiple sites. And even though HN isn't that important, we'd certainly prefer to avoid the headache that would result from someone getting a mod's account, banning a bunch of high-karma people, deleting a ton of stuff, etc.
So SSL is a good solution because a) It could be deployed today. b) It's preferable anyway. But I agree that if they decoupled HN from all the other YC stuff, I'd be a lot less concerned.
HN is not the small and unfamous news site it was 2 years ago anymore.