So. The good news is that IE8 will be much, much better than anything before it. The bad news, Microsoft doesn’t dare release it and make it render existing websites, because there’s no way they’re going to render properly. Why? Because of the browser specific hacks put in to make the site render properly in IE6/7.
A “kill switch” is proposed, which will cause websites to render in the new or updated engine, whilst not breaking existing websites relying on IEs quirks.
Fair enough.
Except that, what if insert <meta http-equiv="X-UA-Compatible" content="IE=8" /> into this website? IE6/7 won’t recognize it, so I can’t really rely on the new CSS support in IE8. In fact, conditional comments are going to be needed so I can load the IE6/7 CSS, and the IE8 CSS, depending on the user agent.
Clumsy, but possible.
The really interesting bit is going to be a few years from now, when IE9 is released. Will I have to insert <meta http-equiv="X-UA-Compatible" content="IE=9" />?. What’s IE8 going to do with this switch? And how different will IE8 and IE9 be? Perhaps I’ll need to conditionally load CSS for IE6/7, IE8 and IE9.
And then IE10, IE11, et cetera…
Seems to me this meta switch is quite reasonable, as long as it kills off the old Trident engine, and activates a proper engine which sees continuous improvement. Much like, you know, modern browsers.
January 26th, Jeremy Keith describes the issue much better than I’d have the patience for. Recommended reading

Microsoft should make fully standards compliant mode the default. People who want to code to a specific browser version can use meta tag when you backport it to IE6 and IE7. Web pages without the meta tag should render in the best way possible, so IE users finally get to see what Firefox, Opera and Konqueror users already have.
If you want to read more: digital-web.com have an overview
A kill switch?
Why don’t they just surrender and follow the standards without thinking about their past sins…
IMHO, Internet Exploder is the worst browser never created.
ok, there is MS’s argument that trillions of old crappy sites won’t render anymore because they’ve benn build for the crappy IE engine, but there actually is a simple solution:
the kill switch should not be added to website code, but to the new browser. and it should work like this:
if the kill switch finds a proper doctype declaration, then the browser should render like mozilla/webkit does, but if there is no proper doctype, then just use the old far-away-from-standards IE render engine.
wouldn’t that solve all of the problems? the web developers, because we can forget to add IE hacks and extra IE stylesheets, and microsoft, because everybody will love the new browser because it works on all sites, be it bogues code or standard comiliant.
We all complain about the IE switch now, but we tend to forget that the problem was caused not by brower vendors but by lazy web deigners, who didn’t keep up with the new standards or desined their sites only for a single browser. Of course the switch is a reasonable solution, but why not just adopt the standards instead? I still see the new IE8 in dark colors.
IE8 maybe is good, but we didn’t yet tasted it in full. I’m greatly doubt we will see something similar to a recent FF. But who knows. Because all nice aspects of a good browser goes directly from open source mechanics – not from a sort of 60+ shiny brilliant software engineers with stable payment.
It seems as though the browser should adapt to whatever site is opened. If it’s an old crappy site, adapt for that site. I probably don’t know enough to make this statement though. This must not be an easy situation. Right?