That's a great idea in general. Not so much in a corporate environment where there may be a piece of older software that is still in use but that no longer requ

That's a great idea in general. Not so much in a corporate environment where there may be a piece of older software that is still in use but that no longer requires active development. In that case, you want to lock the version - you don't want it to suddenly break because of a browser update and don't want to devote additional dev time to a finished product that was working just fine. It'd be nice if browsers automatically updated but could also be forced to run as a specific version (e.g. IE8's Developer Tools lets you run as IE7). Like version control for software (when loading website X, run as browser v2).