Is Internet Explorer 9 an "evergreen" browser? What about IE 10?
Chrome and FF will silently update to newer versions and I've read that MS did an auto-upgrade for folks on IE6 & 7 to IE8 and from IE8 to 9. Has Microsoft stated whether or not 9 and 10 will be pushing out regular (weekly/monthly) silent updates or is it going to be similar to what they did to bump people from 6 & 7 up to 8?
Answer
The latest versions of Chrome, Firefox, Edge, and Safari are evergreen browsers, i.e. they automatically update themselves silently without prompting the user.
Microsoft started moving toward evergreen browsers as of IE10, the first major Internet Explorer release after Microsoft made the announcement it sounds like you are referencing. Through Windows Update, Microsoft automatically updates users to the latest version of Internet Explorer supported by their version of Windows: up to IE8 on Windows XP, up to IE9 on Windows Vista, while IE10 requires Windows 7. Technically, a user on Windows 7 with IE9 (provided they have a local admin account, automatic updating enabled) would be upgraded to IE10, but that doesn't make IE9 an evergreen browser; Vista users stuck with IE9 cannot upgrade.
Regardless, we are now most definitely in a new age of the web, where developers don't have to worry about supporting ancient browsers and can actually use the new features coming to the web platform. For what it's worth, I drew a line in the sand with a web application at Intel to only support evergreen browsers, and it makes me very happy to say so, having gone through the dark ages of supporting oldIE myself.