It would be logical to think that a large organisation would like faults fixed ASAP. After all, why would anyone want faults or security flaws any longer than necessary? You might also wonder why they would not want to make use of improvements to increase productivity.
If you wonder this, have a look at big corporations world wide (including my employer, They are the last users if IE6. Microsoft takes a lot of stick form the technically aware because they did not change it for years. This is because, despite all its flaws, MS is very aware what business wants and that is stability at any cost and this is what Microsoft is good at providing.
The rest of us just need to make sure that we do not install the corporate version of FF.