Here's an interesting article about Gabe and Vale on Forbes. http://www.forbes.com/forbes/2011/0228/technology-gabe-newell-videogames-valve-online-mayhem.html
So it's undeniable that making PC games is very profitable, if you're good at it.Newell says that, per employee, Valve is more profitable than Google and Apple.
So that's $2.8 Billion in sales, last year.Steam controls half to 70% of the $4 billion market for downloaded PC games,
And it's growing at a phenomenal rate, and that's during a recession. Meanwhile console game sales are down.Valve announced last October that it was on track for its biggest year ever, with 200% year-over-year growth.