It’s hard to guage VIsta sales accurately.
It’s not hard to gauge $2 billion a month in profit, though...
Complain as we might, Microsoft DOES do some things right - it’s hard to keep setting records in profit quarter-after-quarter for a few decades unless you’re doing something that people want to buy...
DISCLOSURE: I do some part-time (5-10 hours/week) consulting at the Redmond campus, in a technical field. The engineers there are top notch. I often disagree (and verbally so) with management and business direction, but then again they manage to make over $46,000 in profit per minute, so maybe they do know a thing or two about their business and market space.