Everyone is still digesting what exactly is going on with Avalon, WinFS and Longhorn. Scoble is a great place to start for links to the reaction in general. ChrisAn also has some Q&A on what this means to Avalon.
I think that I can answer some more questions that people might have. I'll take the Q&A format that ChrisAn used.
1. What does this mean for the Avalon graphics architecture as you presented
it at WinHEC?
Actually, things mostly don't change from an architectural point of view. We will have to make some tweaks and compromises to ensure that Avalon runs well on XP and W2K3. All of these compromises will be because we probably won't be able to update any system binaries (User32, GDI, etc.)
2. You said that Avalon had to have Longhorn to work well.
Now it is going to run on XP and W2k3. What gives?
There were some very good reasons for us to restrict Avalon to run just on Longhorn. However, when looking at what customers said and our schedule, it made more sense to bend on some of those reasons than to force developers to wait for wide adoption of Longhorn before being able to write apps. Here are some areas where we are going to have to get creative in making Avalon work on XP and W2k3:
3. How has the Avalon vision changed? Is it a less ambitious plan now?
The long term Avalon vision hasn't changed. We still want to enable the same hardware accelerated, media rich, easy to develop, network connected application platform that we've been talking about since the 2003 PDC. The real change here is a new pragmatic staged approach to getting it out the door and in the hands of developers. If we've talked about some feature or doodad that has to be compromised to make Avalon work under these new constraints, don't worry. Chances are that that feature is still on the list for when we can do it.
4. What is your personal opinion on these changes, Joe?
Thanks for asking! Personally I'm really excited by these changes. It is painful to have to sacrifice (at least when running on XP and W2k3 -- they may "light up on Longhorn") some of the features that require deep changes to the system but the overall result of being able to deliver Avalon to XP and W2k3 outweigh that pain dramatically. Anything we can do to get Avalon out the door on a more deterministic schedule and to deliver it to a wider audience of developers seems like a good thing to me.
Making hard decisions like this is necessary to get big projects out the door. While it would have been great if we had figured some of this stuff out a year (or more) ago, this is better late than never. $50 billion in the bank (or whatever it is these days) is a lot of money but it still doesn't buy you a crystal ball to see in to the future.