The thought did cross my mind, pretty strongly in fact -- but I concluded that at least right now it seems harmless enough and it does offer a pretty good list, after all. Here was the note:
I just posted an article on my blog entitled “100 Best Blogs for Studying the Ocean” at http://publicpolicydegree.org/100-best-blogs-for-studying-the-ocean/ . Anyway, I am happy to let you know that your site has been included on that list. I figured I’d bring it to your attention in case you thought it interesting enough to drop a quick mention about it on your site.
A pretty soft touch for real spam, I thought. Looking through the site, I can't find anything bad. Yes, they are trying to boost traffic, but people trying to build sites *do* want to do that, so that's necessarily a sign of spam. I don't disagree that it's a bit suspicious. This will be a good test... let's check back on this periodically, and see what comes of it!