Microsoft has stuck to its promise in releasing an Internet Explorer 9 Platform Preview update every 8 weeks through the rest of the development phase and has just made available its second preview which you can download over at the IE9 Test Drive website.
The IEBlog page covers all the details about the second preview release pertaining to performance improvements and the implementation of HTML5.
The following video shows off a bunch of new speed oriented demos that are made possible with the preview 2 release.
No harm in giving it a try if you're interested to see for yourself how it performs. It's designed to install and run side-by-side to your default browser.