Put in about 5 hours yesterday.. The game is really really fun despite it's flaws. #1 being communication with other players, but maybe I haven't fully figured that out yet...
It definately suffers from being on consoles, but once you get use to the controls they aren't too bad. The dialog/audio I think is well done, but some animations are a little lacking, such as lip movement and even the way one guy runs.
There is a *lot* to do. It has a very Borderlands feel to it, which I think is a good thing. The Arkfalls are really fun to stumble upon or seek out and complete with a bunch of other players, at the end of them there is a scoreboard which is cool too. You all basically fight off waves of enemies until the end and are then rewarded with loots.
I've only been in one "dungeon" so far in an episodic story. It was pretty fun, and in there I found a one-time use uber weapon that was a blast using.
The skill-grid is confusing, I'm not sure what requirements I need to meet to unlock new skills, but there are a lot of them which is good.. You can mod weapons which is nice but so far I haven't found any worthwhile mods.
You can level up weapon types, like Borderlands, but also specific weapons themselves. Haven't progressed 1 weapon too far yet as I keep replacing it so I'm not entirely sure what it does.
I really like it the combat. It's so refreshing vs. most MMOs where it's all dice rolls. Heatshots, weak spots, dodging grenades, stuff like most shooters have these days are all part of this game. Skill based combat, good stuff.