DX11 cannot be guaranteed to go in any games.
It's entirely up to developers, and if they feel the featured of DX11 are suited for their games. Right now, I"m playing a wot of Bad Company 2. The developers only implemented a minimum amount of features that DX11 enables. They didn't add in multithreading, or tessellation, or a variety of other features that they could have.
DX11 features are up to the discretion of the developer. And honestly, all those extra features and details add cost to development. You can make a crysis type games that adds a ton of details and only high end systems can show all the details available. But why add details that systems can't use? Why add extra development costs that gamers (by and large) can't turn on?
i fear turning this into a flame thread, but perhaps research before posting?
of course we only have small implementations of Dx11 so far, the API has only been available a short time, and a game takes years to produce. the games we have seen it in were near-finished when Dx11 launched, yet devs still chose to include some of its features (a large number of devs so far) which is incredibly promising.
its not about adding features that 'cannot be used' Dx11 offers whole new ways to process graphics, that actually offer performance increases. the fact the Dx11 capable hardware actually has independent tessellation cores that go unused without the feature being active, proves that adding it doesn't mean that system resources are drained. tessellation in fact is one of the more exciting features of Dx11, as it offers great performance increases. or the ability to greatly improve the visual features of a scene by greatly increasing polygon count, as well as adding a displacement map, without requiring huge additional resources.
there is much more to Dx11 than just some new visual effects, so perhaps you should learn a little about it before saying how pointless it is.