Anyone that has installed the new IE9 know if I can keep IE8 installed? I do a lot of web testing and don't want to update to IE9 if I loose IE8.
Per Microsoft:
If you are running Windows Vista or Windows 7 on your computer, you can install the Internet Explorer 9 Beta to replace your existing version of Internet Explorer. After you install Internet Explorer 9, you can uninstall it to restore the previously installed version of Internet Explorer.
So no, it will overwrite IE8 (at least the Beta will. I suppose this is not guaranteed to be the same for the release version).
I use Virtual PC with images of the browsers I need to test, but also and more lately, IETester, http://www.my-debugbar.com/wiki/IETester/HomePage. It allows you to run multiple versions of IE side by side.
If you are concerned with testing how your site looks in IE8/7, you can use the Developer Tools (press F12) to switch the Browser modes and Document modes so that IE9 interacts with the web server as a different user agent, and renders the HTML document according to the version rules.
http://msdn.microsoft.com/en-sg/ie/ff468705(en-us).aspx#_New_Dev_Tools
IE9 beta is released as a Windows update, so after installing it and playing around, you can remove it from Programs and Features -> Installed Updates, which will recover IE8.
If you want to be able to play with the new features of IE9 without installing the entire browser (which will replace IE8) you can install the Platform Preview. The PP is stand-alone, includes the latest features and bug fixes and has been getting updated roughly every 8 weeks. You can get the latest Platform Preview at: