I would say the one thing that could yield additional DX releases is MS's recent support of managed DirectX. If that doesn't ring a bell, it's basically an efficient COM wrapper for DirectX that can be used in .NET.
Quite frankly, I have been extremely impressed with it, save one major issue: there's virtually _zero_ documentation for it. They have documentation, but it's really pathetic...which is really unusual given their track record. To put it into perspective, suppose some API function has some generic "flag" parameter. I'm talking like _no_ intellisense...no MSDN documentation defining the available flag values.
At any rate, I see this as being something that could potentially warrant updates in the near future.