Just a bit of clarification here, as far as I understand it: the one's marked with an 'x' are those that steamspy's system picks up as having lots of variation in the data, suggesting there might be a factor like a free weekend screwing with the numbers. The majority of games in the list marked as such haven't actually had a free weekend, and therefore should be accurate (e.g. Counter Strike:Source). However, there's also some games that have had semi-recent free weekends and which aren't marked as suspicious, such as Company of Heroes 2 and Rome 2.
Yes, i was not sure for many of the listed games, if they had a free weekend recently. But some were making sense. Some franchises like Half Life with counterstrike had the same warning. Fear franchise, Company of Heroes, Call of Duty and some other franchises had the warning. It wasnt (most of the time) just not one game but the whole franchise who had the warning.
Other than that, i want to expand the personal Datapoints of those Million-Sellers with Information about Bundle-Numbers, Steamworks Titles and free-for-all (not bound to Steam) Titles.
Sadly, some People disregard the ownership-data completely if the Game was on a free weekend or in a bundle.
Men of war 2 should trickle out in some days/weeks.