Re: Updates is all that matters...
This is what the web application looks like from the inside of various "enterprise customers" I've worked for.
Back in the dawn of prehistory, several mission-critical requirements were coded as intranet web applications, IE6 was the dominant browser at the time, so everything was written to run on IE6.
In the intervening centuries, the corporate standard browser has been updated to IE7 and the legacy applications have been fixed, but that was such a colossal effort that nobody wants to do it again. In the meantime, lots more important web applications have been written, but they've all been born into a world of prehistoric IE versions, so nobody really knows if they can be updated.
IT professionals within the company all use Firefox or Chrome (they generally have the local admin rights necessary to install them), but development continues to target old IE because that's the standard desktop build. New applications are tested on all browsers, and great unhappiness is caused by how much faster and better-looking they are, even on the latest IE version.
There's a plan to upgrade all the desktops to a more recent IE, but this will involve fixing all the legacy applications. Apart from the expense, this is a big risk, because the people who built them have gone to a better world and the documentation is either fat and uninformative or non-existent.