Pros:
1. new graphics
2. new smoke functionality
Cons:
1. they have removed about 60% of the content from CS:GO (maps + game modes).
2. you can't surf properly.
3. the game is full of bugs.
4. it gets boring quickly due to lack of game content.

I didn't think it was possible to screw up the release of such a successful game. The game is NOT! finished and in my opinion should not have been released. Instead, they should have made an open beta but apparently it's currently the norm to release unfinished games :)...