Now really, it seems to me that MSFT must need to buy some Macs so they can be sure their Mac software actually runs, right? What's the harm in showing a pallette of G5's (some of them knocked over) on a truck? If they poster didn't say it was at Microsoft building, you would be able to tell.
Where I work, we have a Standards of Business Conduct thing that you agree to work there, which I read carefully, and it suggests that giving away corporate secrets will get you into trouble. That's why I didn't post pics of AOL's blogging system while it was in beta, and why I don't make all of the corporate logos available for download in vector format. Those would be obvious violations of trust between me and the company that feeds my family.
IMHO, a picture of a pallette of G5's being delivered to a company that writes Mac software is not grounds for removal. But who knows, this guy could be a major asshole who was on a 'work performance plan' and the company was looking for an excuse. Who knows. I don't, but the whole thing is pretty crazy.