One thing to ponder is popularity vs. authority on a subject.
Let me show you an example. Try a search on Google for "jeff's search cafe" with the quotes so it is a phrase search. There are only 49 matches in Google's index, clearly this is not a popular or ambiguous query -- you are searching for this site (or searching for my non-existent real life cafe).
So, what is the first result: Findory's link to my feed! Second result, here I am. Popularity and Authority. No doubt, Findory has a higher page rank than my pathetic site on blogger.
I have noticed this more and more recently. I have been doing a lot of travel research for my honeymoon (next May is coming too soon!) and I've been exploring hotels and cities and things. What I find quite often is that hotels and cities in Europe (Italy, France, Greece, etc..) obviously don't know much about SEO! Many of the websites for these places are one of two types: fancy art decco flash that looks very expensive, but lacks any substantive content or a quick mom & pop type homepage with simple information and maybe a couple pictures, if I am lucky. Neither ranks well in search engines.
So what do I see most often? I see the the travel sites that review those hotels like Yahoo travel, TripAdvisor, Lastminute.com, etc... My favorite is TripAdvisor, which I actually find quite useful for its fantastic user community. It would be great if TripAdvisor linked to the hotel website, but it doesn't! In fact most of these types of travel guides / sellers do not. It is very frustrating sometimes.
These are two examples where link popularity breaks down. First my blog -- I can't compete with Findory in link quantity or quality. In the travel / hotel instance these are in a similar position competing for link text with major sites like TripAdvisor, Fodors, and their peers. Many are definitely borderline spammish.
How are search engines dealing with this problem? Good Question. I know there was some discussion awhile back about TrustRank. Teoma / Clusty try to help with clustering and refinements. (See also: DiscoWeb rank based roughly on Kleinberg's HITS algorithms). I'll think on this some more later -- its time for some sleep. There must be something better we can come up with.
For now it is just an interesting lesson (and frustrating as I try to plan my honeymoon!). On a side note, I have this intuition that Google feels "spammier", perhaps what I mean is much more commercial, for travel searches than some other types of searches I generally run.