Noprocrast makes hackernews better. Use it.
So I enabled noprocrast today on the default settings (it's on your user page).
Now's the first time I've been on in about 6 hours, and, Wow! Where before I was getting crotechety about the quality of submissions, and starting to want to find a place where the signal-to-noise was higher, now I come here after 6 hours away and oh look, there are tonnes of interesting links here!
So, if you're thinking like I was that HN wasn't quite as good as it used to be, it's very likely you that's changed, not HN.
Try out the noprocrast setting for a week, see how much better HN seems.