Pudge made a cool change in discussions- if you link to a comment deep inside a thread and click 'More' the sytem is much more intelligent about crawling down and retrieving children, and then parents and grandparents and so forth up the ancestry. So odds are you'll get more related comments sooner.
We now abbreviate journals in the firehose... so they are more like slashdot stories with a Read More link to the full text.
The big user facing change this week was structural: historically we had 2 different "skeletons" on Slashdot, but with this refresh we unified to a single one. This change simplifies maintenance for us quite a bit (maintaining the idle section and the firehose views of the same data was a royal pain).
You also will see some changes to the firehose.pl layout. We're playing with the tab layout a bit, moving some menus around and better integrating the core functions into the site chrome. It's a bit buggy atm, so feel free to email me if you see something wonky. We're extinguishing a few minor brush fires but there's no forest fires that we're aware of.