Same great game, but nothing really new...
Underdome: Eh... 6.0
Zombie Island: Fun fun fun... 8.0
Secret Armory: The best! 9.5
Robot Revloution follows the story line introduced at the end of the main original campaign of the evil Claptrap that emerges. This DLC is fun... But it's nothing new. It's the same exact Borderlands gameplay, and it introduces some new enemies. However... All but one boss is just a recycled boss from before. We see Knoxx again, Dr. Ned, and Steele. With a new boss at the end. It's just recycled content.
The most fun part of the DLC is blowing up Claptrap's. It's just fun. The different types of Claptraps that are introduced are amazing. Theres the freedom fighter, the kamikaze, and my favorite the master samurai. They're well done, but come in droves of enemies. Take Skags multiplying out of the same hole and multiply it by 5. It's a little much at times, but fun.
The most disappointing part of the DLC is that it is extremely short. It took my just over 3 hours to complete the main story line, and I'm now working on the side quests and new additional achievements. But it was just short. It would be ok but it cost $10. If it was a little cheaper, then I'd be ok with the amount of time it took. But that's not the case.
Overall, it's fun. Borderlands fans should definitely pick it up and enjoy the time you'll have murdering countless claptraps. And newcomers will get lucky by having this DLC included in the GoTY edition coming out. It's a good DLC, but it's not the best one that Gearbox has released.