One other session I attended on the last day of MIX06 was the sparsely-attended 8:30 AM RSS Platform Presentation.
One of the folks from team RSS was there presenting about the new RSS functionality in IE7 as well as the new RSS API which will ship with IE7.
Overall, I think the API and the concepts behind it are useful and well executed. However, IMHO, they did a few dumb things with the API:
Written in Native Code as a COM Interface
They wrote it as a good old C++ COM interface that is .NET friendly. It would have been nice if they had written it in .NET and simply provided a CCW into the code. They said that they did it this way so apps would not have a dependence on the .NET CLR.
Packaged with IE7
Since the RSS API is not tied to IE7, I asked why not ship it separately? Many clients have a hard time accepting that a new browser is required to support your rich client application. It's a psychological thing, especially if they use a non-IE browser for their day-to-day work. Someone else seconded the request, and they "will look into it"
No RSS Server Equivalent
They wrote the code in such a way as to only really work on the client. However, the object model (which can parse RSS feeds) could be used to generate the feed if they had taken that extra step. Some folks there asked about that functionality, and the presenter actually seemed surprised when asked. If RSS is to be a new technology for getting dynamic information out to users, and is to be more than "just blogs and news", as he kept saying, then a server-side piece is needed. Thsi is especially important as the RSS API will only accept well-formed and valid RSS / Atom XML.