Re: Damn right
"Preinstalled"? Then someone, somewhere in Microsoft installed it for them. And someone, somewhere was writing the code for the installers and (presumably) testing them. And someone, somewhere wrote the code for the window that was supposed to pop up and (presumably) testing it. And someone, somewhere was installing it on lots of new hardware from disk to check things like disk images, hardware, installers, drivers, etc. worked as expected on bare hardware. And someone, somewhere was writing internationalisation data for the installers and (presumably) testing it. And someone, somewhere was presumably testing slipstreamed installs, PXE installs, "first-time" applications, and a range of other things.
And MS employees are allowed to install any OS they like on their PC's, if previous articles are to be believed, and thus they would have been installing it somewhere all the time, given the number of employees.
To even try to claim that Microsoft weren't installing their own product would be hilarious for them. And if they weren't, it leads right into wilful violations and inadequate processes to monitor those violations.
"We did what the court asked last time."
"We don't know, we never bothered to check."