They gave up Windows XP with IE 9. Keeping the same trend, they are giving up Vista with IE 10. In fact, Microsoft is actually getting worse. They are already treating Windows 7 users as second class citizens. IE 10 for Win 7 will only get a preview release in mid-november. Final release will probably come a few months after that.
In comparison, Opera still supports Windows 2000, although it recommends at least using Windows XP.