don't really agree.
Companies should only do the upgrade when their current OS or network can not handle the work they need. or it costs too much for maintainance and external support, or too much down time. they don't need to upgrade the OS just for licencing mentioned(renting instead of buying) or the new OS is better or has got more functions, since their current OS is still fine. OS or software are made to fit business use and need, remember that.
From leescot@excite.com