I almost don't know where to begin with this. The pressure is building on Longhorn to be more than magical. Does Microsoft not know how to deliver an evolutionary set of products and services? Is this self-destructive engineering or brilliant business? Or something in between.
Alan also told me that one of his goals was to come up with a unified model for accessing data across most Microsoft programs. It would be nice, for example, to be able to load up Microsoft Money data the same way you can in SQL Server using ADO.NET. If you put aside the emotion and really think about it for a second, that's one of the key reasons they're putting WinFS into Longhorn, to remove the "program-specific silos" that happen in application development today, and allow WinFS to be not only a file storage system, but an information storage system as well...
Microsoft wants to make ObjectSpaces the way IT'S OWN teams get data out of WinFS in the Longhorn time frame... And for most, normal, sane people, this makes a decent amount of sense.
So, ObjectSpaces is an important technology. Microsoft wants to get it right in V1. With every product being relied upon it when Longhorn comes out, they almost don't have a choice in teh matter. They don't want to have to wait for it to be usable until V3, like most Microsoft programs, they want it done right the first time. And that's admirable. It's not like you're not going to see bits shipped in beta form between now and 2006. You'll still get to use it, so what's the big deal?