I haven't quoted any articles from blogs, the figures are taken from a site that scrapes Steam user profiles and aggregates them. Figures from the PCGA indicate that retail and digital download sales were on a par for 2008 and DD would exceed retail last year. As an example, CoD4 sold 360K at retail first month. IW have stated that CoD6 exceeded CoD4's first month, yet NPD gave the retail PC figure as 170K- the other 190K+ must have come from DD.
PC gaming is more relevant than ever these days, 25 million Steam users prove that.
As for piracy, Crysis sold over 1.5 million. Are we seriously to believe over 30 million people downloaded it?