Personally, I have to heartily disagree with this:
ALWAYS provide text links for linking to your site. Avoid image links.
Google does index image links, but without any text for it to index, it won't help your link popularity rating for your important keywords.
In my experience, image links are just as effective as text links when you use the same keyword phrase in the image alt attribute.
I don't like the idea of telling people that they shouldn't be using image links as they are the cornerstone of most Web pages. They're just as effective from what I've seen. I'd want to see the author's data that shows they're not as effective, when created in a similar manner as a text link.
I also feel that the article gives PageRank a lot more credit than it deserves, but I suppose that is a matter of personal opinion.
I do agree with Chris that the piece was clearly an opinion piece based on the author's own research, and I feel that was perfectly clear. And yes, not unlike the way I write my own Advisor articles.