Six months ago Microsoft issued this statement:
As you may have heard by now, Internet Explorer 8 will ship with three layout modes – Quirks, IE7 Standards, and IE8 Standards. The saying goes: “put your best face forward” and, true to this, Internet Explorer 8 will use its most standards compliant mode, IE8 Standards, as the default when encountering standards content.
Now, with the release of IE8 beta 2, it seems that statement is less than true; for intranet sites at least. Even when a site is completely standards compliant, if it’s on an intranet, IE8 will render it in compatibility mode by default. According to the article(see link below) roughly 60% of computers sold go to corporations with the remaining 40% going to home users. So, when you load the corporate homepage from your desk at work(internal) you will see it differently than a user loading it from the internet(external). EVEN IF the page is completly standards compliant with DOCTYPEs and everything.
Apparently, it’s not exactly easy to fix either. It’s just a checkbox, but it’s in an odd place and has a confusing description for the average user. To make matters worse, your page will have an icon next to the address bar that shows a broken page, just to.. you know.. cause more confusion: