Directx 11 has been confirmed. Microsoft is planning to announce directx 11 at Gamefest 2008, previously known as Meltdown which takes places in less than two weeks. Gamefest 2008 takes place on the 22 and 23 July in Seattle, Washington and you can find some more details about the conference at xnaGameFest.
According to Fudzilla
The big feature of DirectX 11 is Tessellation/Displacement while we also heard that Multithreaded Rendering and Compute Shaders are part of it. DirectX 11 also brings Shader model 5.0 but we donâ€™t know many details about it. It looks like DirectX 11 will stick to rasterization as there is no any mentioning of Ray tracing support. Nvidia will also talk about DirectX 11 at its Nvision event / conference in late August 2008.