Borderlands is one of the most awesome games I have ever played. I got into BL1 on the 360 about 3-4 months before BL2 launched. I originally had no interest in it as I am not a fan of sandbox style games with inventory management, skill trees, etc. I typically go for the simple FPS games with a deep story like Halo, COD, Bioshock, Half Life, etc. However, I kept hearing how great BL1 was over and over again and just broke down and picked up a used copy of BL1. I preordered BL2 the next day.
From a technical standpoint it is a great FPS. The cell shaded almost comic book style look is great. I thought it would make the game feel cartoonish, but I was wrong. Inventory management is pretty easy even though there are literally hundreds of thousands of different guns, shields, grenades, etc.
The game is pretty simple from a story standpoint, but the humor is dark, yet silly and almost on par with Portal.
The season pass with all 4 DLCs is well worth the $30 I paid for it. The first three are pretty basic add on campaigns, but the final one, Tina Tina's Assault on Dragon's Keep, is worth the $30 by itself. From what the publisher is saying, the 4th DLC is larger than the other 3 combined in every respect and the story is a hoot especially if you played D&D or role playing games like it in the past.
In all probability I will be playing BL2 for years to come, or at least until they come out with BL3 as there are a total of 6 character classes and I have yet to max out my first character.
I play it on PC, but this choice was mainly due to the fact that I can get on my PC much easier than my 360. My 360 is in the living room and I have to kick the wife and kids out if I am playing on it. This is no big deal for an 8 hour single player campaign, but is next to impossible for a game like BL2 that you can easily put hundreds of hours into. No one else in the house uses my desktop so I can play almost anytime I want.