Included in the design is support for CSS3 in the older Internet Exploder versions 7 and 8. With the release of 9 and it natively supporting CSS3 we have started to code and release more Shape 5 CSS3 compatible designs. The problem was that IE7 and 8 don't support CSS3 out of the box so we came across CSS PIE (Progressive Internet Explorer). Basically put, its a script that upgrades IE7 and 8 to support most CSS3 formatting. There are slight variations and some CSS3 formatting it doesn't support but overall it does a great job and allowed us to make the decision in switching over to CSS3 without sacrificing the user experience in IE7 and 8.

Overall this month the design is almost fully identical to Firefox, Chrome, etc in IE7 and 8 besides the top drop down and a few other small formatting entities

More information on PIE can be found here:
http://css3pie.com/