I work in that industry. Hes still right. I work at one of the largest movie, tv, media conglomerates in the world and the Mac users and small because Apple cannot offer the business what Microsoft can. Now we do have macs but its around 2500 Macs oppose to our 45000+ PC's.
I do not work in LA, but I work on TV commercials in a major European capital and when I go to work there is a lot of Macs. From directors, to DPs, to gaffers, to producers, and PAs.
Going past that I'm sure there are plenty of PCs in use for a wide variety of uses. However to my knowledge Microsoft doesn't have any dominating editing suites, or post & SFX apps. I'd hardly say the professional market belongs to Microsoft.