On the heels of Phil Windley's post (I commented here) comes Bob Wyman's post on the same subject. In response to Marc Canter, he says:

Marc Canter ... mentions that PeopleAggregator will support a wide range of "identity" systems ... Basically, if a system exists and has anything to do with identity, Marc's folk appear to intend to support it...

This is a rather drastic but very rational departure from the customary practice of only supporting a single identity system per site...

I think Marc has been talking about this at least since last summer, but of course I very much agree with the sentiment. Protocol wars are for geeks and we-will-take-over-the-world plotters, interoperability is what matters to the end user. Which is why MyLID.net and NetMesh InfoGrid are now multi-protocol, already supporting three identity protocols in the same easy-to-use package.