By moving to IE9 he's discounting all corporate customers who haven't moved to Windows 7 yet.<p>This leaves them with only one option if they want support on a long-term supported browser, which is the recently shipped Firefox Enterprise Support Release.
I think the title is a little bit misleading. The moment you can drop support for browser versions is pretty dependent on the requirements of your client, and your visitors. 7% for users with IE8 or lower is a pretty tech-savvy crowd, many developers might not have the luxury of dropping support for IE8 because many of their visitors still use that browser.
I'm so sick of websites not even attempting to render in a browser not in their whitelist. Please give me a button that says "I understand the risks, but I want to try anyway."
The multibillion dollar organization I work for just updated to IE8 from IE6 last week. We aren't allowed to use new browsers or chrome frame for "security" reasons. ha!
My understanding is that IE has a significant market share among users with accessibiliy needs (came up in conversation after the recent jquery 2.0 browser support discussion). While that may not be important for 37 signals it's an oft overlooked side effect of dropping version 8 support.
Now the problem becomes mobile browsers...
(hover vs. tap, tiny resolutions, differences in form controls, sometimes crippled features that work fine in a "pc" based browser, fluid layout choices, float issues)<p>There will always be madness.<p>[edit] Took me a few to find this link again. Do compatibility charts like this look familiar? <a href="http://www.quirksmode.org/m/css.html" rel="nofollow">http://www.quirksmode.org/m/css.html</a>