I was about to make a post about how idiotic it was for people to refer to Josh Koscheck as a "Top Five Welterweight" then I had a moment of clarity. It's the weakest weight class in MMA and he actually is (was) in the Top 5. In no particular order after GSP, you have Thiago Alves, Jake Shields, and Jon Fitch. After them you're left with Matt Hughes, Koscheck, Carlos Condit, and Mike Swick for the fifth spot. BJ Penn and Diego Sanchez are not apart of the conversation.
To give you an idea of how the Welterweights compare to other divisions, here are some names from the top of the Middleweight division: Anderson Silva, Gegard Mousasi, Dan Henderson, Robbie Lawler, Yushin Okami, Demian Maia, Nate Marquardt, Michael Bisping, Vitor Belfort, Ronaldo Souza, and Jorge Santiago. And that's just some of them. I could also mention about 5-7 more.
When did this happen? Even the awful Heavyweight division is deeper with Fedor, Lesnar, Mir, Couture, Nogueira, Barnett, Overeem, Velasquez, and Gonzaga.