If you sort by new at the very top you can see posts that say they were submitted an hour ago, then a few posts down it will say minutes ago. This happens with comments too, I've seen comments that say they were submitted minutes ago but a reply will be submitted an hour ago.

I just posted a comment and it showed up as an hour ago. Is this timezone fuckery?

Edit: happened to this post too. Just submitted and it says an hour ago