I don't get all this bashing people just because they like IE. Get over it.
I've dabbled in web design a little so I *know* you have to jump through hoops to make your sites look pretty in IE aswell as the other browswers, but for actually using the internet I don't see what difference it makes what browser you use so long as you are comfortable with it. I favoured Firefox on Windows then went Mac and used Safari until it started grinding to a halt. Now I use Chrome almost constantly and i'm very happy with it, but I don't see any reason to start flaming anyone for using IE.
At the end of the day, all software has its good and bad points, and people learn and problem-solve differently, so naturally they will find different software to their liking. Personally, despite all the rave reviews of it, I still don't 'get' the Gimp. It just isn't the right fit for me (possibly that is just the Mac version though which doesn't feel like a native app). I don't see that it matters what developers think is the superior browser: Regardless of the technical whizzbangs under the hood, the only thing that matters is that people can actually use the thing and enjoy doing so.
I do agree that users should be encouraged to upgrade if necessary, without rapping them across the knuckles for using a browser the developer doesn't like. It would be impractical for companies to support older software indefinitely. How effective this gimmick will be is doubtful though.