What can I really say? PAYDAY 2 is better than its predecessor in every. single. way. They've made the game become slightly more RPGish--with specialized skill trees and the ability to craft new weapons and masks--and a lot more realistic, too. If you played and enjoyed the first one, you're gonna worship the second.
Oh, and did I mention the beta went live today?
Go pick it up and perform some dangerous heists!