Seems like a perfect solution, plugins as a way to reuse code.
Reasonably good list of upcoming conferences/events for 2011
IE9 Release Candidate has been released, if you were using the Beta, grab this update to see the feature complete product, and provide feedback to Microsoft before final release.
Contains links to the VHDs provided by Microsoft, as well as link to instructions for setting up multiple XP Modes on one Win7 machine to test IE6, IE7, IE8, and IE9.
Click in to find related links.