I played Crysis 2 as soon as it was released in March 2011 and have now read this book. All I can say is that it's a superb read! It fills in the gaps in the Crysis 2 story that are a little vague when playing the game itself. The book is very well written and follows the main character in the game (Alcatraz). It follows the story in the game pretty closely, with more focus on the story than the action (obviously). There is a lot of dry humour in there, which appeals to me! Note that there is also a LOT of swearing, although it fits in well and I didn't find it offensive.
Recommended.