There doesn't seem to be much to it other than shooting the various creatures that inhabit Pandora, though you are able to bring experience and loot, including Moxxi's Rocket Launcher, back into the core game. So, unless you are a completionist, I wouldn't worry about needing this content.
You know what would have been even better for the game to include? A pleasure dome.
Get a closer look at the four playable characters in Borderlands: The Pre-Sequel
8:00 AM on 09.15.2014
Claptrap shows off his action skill(s) in this Borderlands: The Pre-Sequel trailer
5:00 AM on 08.13.2014