99% of John Gruber posts are glowing reviews of Apple products. His blog is essentially promotional material for Apple. I'm not sure why people post his articles here.
He's definitely an Apple enthusiast, but he doesn't pull his punches when he thinks Apple has made a misstep. His criticism come from a place of love for Apple: he wants Apple to be great, but that's not quite the same thing as being a paid publicist for Apple. I don't think it's fair to call him a shill.