Nick Bradbury has a post entitled Feedback on IE7 Beta 2 from the Developer of FeedDemon where he gives a lot of good feedback on the recently released IE 7 beta from his perspective as the developer of an RSS reader. Although I've given some feedback on the RSS reading functionality of  the IE 7 beta, I realize it would be more valuable to give my thoughts on the Winows RSS platform since this is supposed to make the job of people like me who've built RSS readers better. Below is a smattering of feedback divided into pros and cons of using the Windows RSS platform versus using the version we've built for RSS Bandit. Note that as Nick says in his post given that I've already written a lot of the ugly code needed to handle feed downloading, caching, parsing, etc. actually switching to use the Windows RSS platform is a load of unnecessary work for me. My feedback is based on the kind of support I'd need from the platform to implement the scenarios currently supported by RSS Bandit .

PRO

• COM API  was very straightforward to interact with from  .NET applications
  
• Built-in support for downloading enclosures in the background is nice
• Good support for asynchronously downloading feeds. This means application developers don't need to write a bunch of multithreaded/asynchronous code themselves. That is definitely a godsend.
• One can serialize feed objects to  XML
  

CON

• No support for application specific feeds. The Common Feed List assumes that user needs to use the same list of feeds in the various applications used for subscribing to feeds. I think this assumption is fundamentally flawed. I might use one application for downloading podcasts (e.g. iTunes), another for reading blogs (e.g. RSS Bandit), and yet another for browsing photo feeds. Since it doesn't make sense for my blogs to show up in iTunes, it would be cool if I could identify either the type of feed (podcast, text-based, etc) or the favored application for reading the feed via the API.
  
• No support for password protected feeds. The number of password protected feeds on the Web continues to grow, Web sites such as GMail and LiveJournal provide authenticated feeds for users today. As the usage of syndication technologies like RSS continues to grow, the need to support authentication by feed readers will also grow as well. I can imagine a day when I can subscribe to a password protected feed from my bank or credit card company. Not having support for this today is a non-starter.
  
• Support for obtaining XML elements which aren't supported by the API. It would be nice if there was a property for obtaining extension elements in a feed that didn't involve having to convert the feed object to XML then using XPath. Being able to perform a call like  Feed.GetItem("http://wellformedweb.org/CommentAPI/ ", "commentRss") to get an element which isn't mapped to a property in the Feed object is a lot more desirable than writing DOM or XPath code to extract that element from the results of calling Feed.Xml
  
• No ability to append application specific metadata to feeds. RSS Bandit supports notions like flagging items and we'd need some way to indicate that items are flagged if we are using the API.
  

Most of this is just based on reading the Using the Microsoft Feeds API document on MSDN. I'm sure I'd have more feedback if I took a pass at replacing all the feed processing code in RSS Bandit with the Windows RSS platform. However I don't think I'll have time to do that anytime soon.