Ben Laurie has issues with the Microsoft purchase of Crenditica that deal, ironically enough, with trust. Specifically Ben does not trust Microsoft to make the U-Prove technology interoperable with other products. Also playing a part in this is Microsoft’s strange reluctance to support identity standards that they did not create (SAML for instance). This position does little to endear Microsoft to experts in the identity community.
Yet on the other hand Microsoft identity experts such Kim Cameron, Mike Jones, and (now) Stefan Brands are held in the highest regard in the community. They are known to be strong supporters of openness and interoperability. But the obvious fear is that as honorable as their intentions may be, they are only in a position of influence, not control.
What is a vendor to do?
What you should do is trust that Microsoft, like every other company, will behave in accordance to the law in a way that will increase their profits or market share. To expect any company to do otherwise would be unwise. This may sound obvious, yet I often hear debates in this community that boil down, in essence, whether a companying is being “fair” or not.
That said, I expect Microsoft will make the specification underlying the U-Prove technology freely available for other vendors to use. With the standard restriction that the non-assertion convenant applies only to using the specification for interoperating with U-Prove and other U-Prove compatible technologies. If recent history is an indicator I suspect they will also sponsor interoperability events and give you technical assistance implementing the specifications. I have personally been involved in an such efforts around WS-Federation (pre-OASIS) and Cardspace and the experiencees were very rewarding.
Microsoft won’t renege on any of it’s promises simply because it would not be in their financial best interest. As valuable it is, getting widespread adoption of U-Prove is going to be tough. Microsoft is going to need the participation of other vendors to do it.