I have been working in Internet Explorer 7 and 8 compatibility issues for the past little while.
And, I am surprised by three things;
How complex getting a Web-App working on both server and client really is
How many companies/organizations are moving a web based application portfolio
The layered stack (OS/Middleware/Security/Application) is more important than I thought
This is a huge topic, for which Microsoft has ladled out copious quantities of documentation on IE compatibility including samples and scriplets. The best place to start is the Microsoft MSDN compatibility "Start Page" located here: http://msdn.microsoft.com/en-gb/ie/dd433173.aspx.
Even better, here is the link for the developer compatibility site for IE8 on Microsoft's Developer Network (MSDN):
Having to start somewhere, in determining if your application is compatible with Internet Explorer 8, you can see if your web site is in the "Sin Bin"... Or the more diplomatically, your website has been included in Microsoft's non-compatible web-site list. At last count, there were over 3,400 sites included in this "Bad Web manifesto".
You can download the Microsoft XLS spreadsheet that includes these sites from here: http://go.microsoft.com/fwlink/?LinkId=145413
To find out more about the IE8 compatibility view and this list, look here: http://msdn.microsoft.com/en-us/library/dd567845(VS.85).aspx
This list is updated roughly every two months (apparently in sync with Microsoft Security updates on Patch Tuesday). If you have already installed IE8, then could see the XML representation of this list simply by typing the following URL into the IE8 browser windows; res://iecompat.dll/iecompatdata.xml
Here is a brief sample of the "Bad" websites generated by loading this local RES URL on my laptop with IE8 already installed;
So You Don't Want to be a Programmer After All
3 weeks ago