He's more of an average Joe than a power-user. Maybe my definition is wrong, but I think one of the qualifiers for being a power user is knowing how computers work. He admits in the review that he doesn't really know anything about computers unless it has to do with making awesome cartoons.
I'd argue that not being a power user is what makes him such a good spokesman for Microsoft.
I define "power user" by what they do, not what they understand. I consider him a "power user" because his workflow goes beyond the standard browse the web, send email, write some Word documents. He uses a suite of programs specific to his profession and has a workflow situated around those programs and the OS.
I'd argue that not being a power user is what makes him such a good spokesman for Microsoft.