It's now been over two months since Google et al. announced support for <link rel="canonical">, so I thought I'd do a spot check to see who's using the new <link> tag attribute and who isn't. As you'll see, so far the response has been, well, underwhelming.
Not observed. But…
Blogs and Social Media
<link rel="canonical" href="http://technorati.com/" />
Not observed. No 301-driven canonical domain name, either (see my note on nytimes, below).
I added this category because online gaming sites are supposed to care so much about SEO.
Media and Gateway Sites
Not observed. Just as an aside I pasted all of the above URLs because, aside from not supporting the <link rel="canonical> tag, nytimes.com isn't even doing supposedly industry-standard 301 redirects to posit canonical folder URLs and – gasp – a canonical domain name. Marshall, baby, you're my hero: what gives? :) At least it's there for about.com.
If you were counting TLDs, you'd see that 36 sites aren't employing the tag, and two are (one and a half, really, since only one of the google.com URLs I checked was carrying it).
Make the nay count 37 if you add SEO Skeptic. By the way, I'm actually a proponent of the tag, but haven't got around to employing it here (after I upgrade, after I upgrade). Of course, with WordPress, I'd need a plugin, so did a quick search: sure enough, I found one on yoast.com. And that brings the "yea" count three (or two and a half):