A new version of SlimDX is now available. This version wraps the latest DirectX SDK release (August 2009, thus the name). This means that things like DirectX 11 and Direct2D are now officially supported (previous releases were beta).
You can download the installer here:
You can also read a little more about this release at the GameDev.net forums:
I'm looking forward to trying it out. Unfortunately, I still don't have DX11 hardware, so I'll probably hold off on things like tessellation or the compute shader.