"The biggest hurdle may be cultural. A version of Office that puts people first, not applications or data, has to revive Hailstorm. Software that does what we want has to know what we want. If we want to be interruptible by family members but not team members (except in emergencies), we have to represent ourselves, our family, and our team as, pardon the expression, first-class data objects. These avatars need to live outside the realm of existing applications and directories where any authorized service can talk to them. Microsoft got smacked upside the head when it first floated this idea, and not without reason.
The most critical piece of Internet infrastructure since the DNS really shouldn't be a Microsoft business unit. Now, happily, everyone's singing in the federated identity choir. But the fact remains that to make the concept videos real, we'll have to schematize ourselves as well as our data, and we'll have to trust someone with those schemas. Assimilating XML and .Net into Office are only technical challenges that programmers will sooner or later solve. Rehabilitating Hailstorm will require what Microsoft famously lacks: social skills."