GOSSIP has a few new things. Delegation (NIP-26) support was added (although shallow, it needs to be deeper still). And there are more Feeds. The feeds will change as we work out the proper UI/UX, but for the moment they mean this:

Main feed - the people you follow, top level posts only

Conversations - the people you follow, including their replies to other threads

Inbox - notes that are direct replies to your notes, or that mention you in the contents

Activity - all notes that tag you, even if you are not mentioned directly in the contents or they are not direct replies (including hell threads)

I know that's not obvious, which is why we are still designing.

Hat tips to #[1] and #[0]