An avid Apple and open source fan. I've recently come to see how much of a contradiction that can be.
That said, I don't think an open-sourced version of Microsoft's enterprise intranet newsfeed network thingy would be terribly exciting. I would suspect that it would be highly specific to the structure of their intranet and would be tightly coupled with AD and MOSS. Likewise, I'm sure it needs to scale but being a closed community means that it doesn't need to scale that much compared to something like Facebook.
Profiles. Friends. Those are probably the easy part. I suspect if you wanted to use a non-AD system, have an open web standards-based product and increase the scale or build on top of an existing open source intranet platform then you would get more mileage from ground zero.
That said, I don't think an open-sourced version of Microsoft's enterprise intranet newsfeed network thingy would be terribly exciting. I would suspect that it would be highly specific to the structure of their intranet and would be tightly coupled with AD and MOSS. Likewise, I'm sure it needs to scale but being a closed community means that it doesn't need to scale that much compared to something like Facebook.
Profiles. Friends. Those are probably the easy part. I suspect if you wanted to use a non-AD system, have an open web standards-based product and increase the scale or build on top of an existing open source intranet platform then you would get more mileage from ground zero.