What are some good Object Oriented 2D graphics API?

SFML(Simple Fast Multi-Media Library), works best in VS 2008, It can be re-compiled to work in VS2012 or 2010

Just curious but why do you need it to be Object Oriented? Otherwise there's SDL a library that does 2d graphics and more that I use quite extensively with C++ although it's technically C and therefore not object oriented.

You do not need to program object oriented, but it makes development faster and easier(C is actually capable of OOP). SFML and SDL are pretty similar in concept, SFML is just newer and provides "fancy" features like networking. I would try out both SDL and SFML and then choose which one you get a better feel for, they are both equally capable of producing high quality games.

The practical difference between OOP and non OOP in a nutshell
gun->shoot( ); // OOP
functionShootGun( &gun ); // non OOP

Besides a bunch of inheritance functions that can make life easier (but also worse if poorly implemented). I'd say it doesn't really matter in the end, just as long the library you'll be using is cleverly set-up, providing examples, and documents. DirectX is OOP I believe, OpenGL is non OOP and works like a state machine. And both kick ass.