Re: 40 years of leassons learned
@mejac, I don't see that changing, certainly not at our company. Enterprises care about getting work done, which means applications, not o/s. I would argue the last o/s reason for enterprise productivity was either Active Directory or Group Policy support. You could also throw in, from the old days, the ability to boot faster and not crash on users. But for most part, that problem ended with XP and Pentium 4.
Now that core o/s doesn't bring anything new (like AD) to the table, every upgrade is just a cost exercise to get your applications running on new version, plus any user training. Win 10 should at least minimize training effort (over Win 8 with no Start button) and Win 10 should run most Win 7 apps without requiring upgrades. I think biggest thing to watch will be this new browser, how backwards compatible it is for IE apps. For example, we still run WSS 3.0 (free Sharepoint), how's that going to do with this new browser geared for HTML5?
So I'm suspecting end of support for Win 7 will again drive upgrade. If anyone in enterprise space disagrees, I'd be very curious to hear your thoughts why you would go sooner.