Thanks for testing the Internet Explorer 9 Platform Preview #1 (IE9 PP1). As we announced at MIX, the IE9 PP1 is a way to try out the platform and to experience improvements we’re making to performance, standards support and interoperability, enabling “the same markup” to work.

It’s not complete. We are NOT done yet. We have MUCH more coming in the next releases (including, but not limited, support for the video tag) :-)

Looking at your tests, I have a question for you. In your previous blog post, you stated “the HTML5 standard and other related specifications are still in development”. I agree with your comment; in fact Microsoft, as well as other browser vendors and in general all the W3C members, are working together with that exact goal: move the HTML 5 specification (and CSS, DOM, SVG, …) forward.

Let’s take for example the Web Workers Working Draft. The W3C defines it “not stable” (“Implementors should be aware that this specification is not stable” , from W3C HTML 5 Web Workers link on your blog). In fact each browser is implementing this spec with a different model in mind (for instance, I believe Firefox doesn’t allow you to terminate and restart a worker). In this scenario, what is your test testing?

The risk is to set wrong expectations with developers – since the code they write today, might (and probably will) break as these specifications change based on the current discussions happening in the W3C group.

The audio/video codecs are a different interesting topic, as you mentioned earlier. Giving points to the browser that supports more of them would not serve the scope. Can you imagine if a browser would support 5 codecs, and another browser other 5 different codecs? That would create even more fragmentation (for the developer, for the user, for the tools, …). I wish this was an easier problem to solve and I’m looking forward to a Web where all browsers support the same codec. :-)

That said, we *love* HTML 5. And we are working very hard to make the web developer dream come true: “code once, run everywhere”. Interoperability (as showed by the corner radius demos) will be a key component to the success of HTML 5. Performance also will be essential to enable great developer scenarios. Check out for instance our blog posts from Jason Upton, our IE Test Manager, and Jason Weber, our Perf lead, talking about tests for web standards and performance:
http://blogs.msdn.com/ie/archive/2010/03/17/test-drive-104-new-professional-grade-tests-for-web-standards.aspx
http://blogs.msdn.com/ie/archive/2010/04/07/a-closer-look-at-internet-explorer-9-hardware-acceleration-through-flying-images.aspx

If you believe we have bugs in our implementation (which is most likely possible right now :-)), or you feel like we are missing something, feel free to contact me or to file a bug on our open tracking system. Any feedback you might have will be much appreciated!
http://blogs.msdn.com/ie/archive/2010/03/25/filing-a-great-bug.aspx

Btw, you should expect the next build to come in about 4 weeks!

Best regards,
Giorgio Sardo
Microsoft IE9 Technical Evangelist