Now, back to the main topic. So many people hate on how linear C2 is, and how it became too much like CoD-blah blah blah. What most people don't realize is how linear C1 was as well. While it was less linear than C2, it wasn't to the point to make a big deal out of it like most people are doing. While you could free roam the island, there wasn't too much to find. The mission structure was VERY linear (excluding the tank scene). Most of it is even a one path mission approach. Think about them. Also, people think linearity is all about a horizontal plane (meaning most building or enemies are just on the ground). While C1's horizontal plane was much larger, C2's was much more vertical. When playing C1 I can't really recall a whole lot of time's when I was in a building sniping from a window or doing a surprise attack from above.
I can understand some of the complaints such as lack of game modes or vehicles. But I really think the linearity complaint is silly, and mainly used as a complaint to try and put themselves above console gamers.