If you've played EVE Online using Singularity, our public testing server, you may be running with DirectX 11. The change should be mostly unnoticeable, as our goal right now is to have a DX11 client that performs the same (performance, stability) as our DX9 client. This change will go out to everyone in our winter expansion, EVE Online: Rubicon.

DirectX 11: What to expect – EVE Community
community.eveonline.com
Eve Online is the world's largest MMO RPG universe rich in adventure, as player corporations compete in a massively multiplayer online space game.