Regarding jim boykin having sitelinks vs matt cutts, pronetadvertising, and sel having none, perhaps jim boykin reaches more newbie-nontechnical readers (eg people typing in jim boykin into search engines) than those other sites; although a flip side of that is: whoever clicks the links “Microsoft Land” or “Google Land” while on SEL? They aren’t that useful/aren’t a destination. matt cutts blog is the only destination on his site as well.
Maybe it’s both, a correlation of volume of searches combined with toolbar clicks.

Will we ever know with certainty? Probably not.

although since sitelinks generally come up for a company’s name it probably doesn’t make much difference.

It is good because searchers will automatically assume the site/brand can be trusted.

Obviously, as something that is determined by an algorithm, the quality of the site in Google’s eyes is going to be a bit of a loose factor.

Throwing up a few here that will almost definitely be seen as low qulity sites but have sitelinks:

wank.net – youtube for porn, including the sitelink “Skank Gets Her Ass F*cked By” – PR4
crackzplanet.com – PR4
http://www.warez.com – PR6
http://www.hightimes.com – PR5

All of the above have good traffic and the visitors probably spend a lot of time on the site

but then Dean Edwards doesn’t have them with a PR8 and undoubtedly a low bounce rate and high traffic.

Messy URLs doesn’t seem to cause any problems either: al-jazera

So, a bit of a mystery.

A method, comprising: receiving a search query from a user; generating search results based on the search query; identifying a plurality of web pages associated with at least one of the search results based on a quality factor associated with the plurality of web pages, wherein the plurality of web pages and a web page associated with the at least one search result comprise web pages in a same web site; and providing the search results and a plurality of links associated with the plurality of web pages to the user.

What is this quality factor?

4. The method of claim 1, wherein the quality factor is based on a number of times each of the plurality of web pages has been accessed.

5. The method of claim 4, wherein the providing a plurality of links includes: providing the plurality of links in an order where a link to a more frequently accessed one of the plurality of web pages is listed before a link to a less frequently accessed one of the plurality of web pages.

6. The method of claim 1, wherein the quality factor is based on an amount of time a plurality of users have viewed each of the plurality of web pages.

7. The method of claim 1, wherein the quality factor is based on a number of web pages with a link pointing to one of the plurality of web pages.

8. The method of claim 1, wherein the quality factor is based on a score associated with how closely the search query matches information contained on each of the plurality of web pages.

9. The method of claim 1, wherein the quality factor is based on items purchased via each of the plurality of web pages.

10. The method of claim 1, wherein the quality factor is based on the user’s prior behavior with respect to the plurality of web pages.

How can they tell how many times a particular page has been accessed, how long a user stays on a page, etc.?

[0042] Processing may begin by log processing system 125 receiving data via network 140 (act 610). For example, front end 310 may receive data when clients 110 access various web sites. In one implementation, assume that users have downloaded/installed a toolbar on their respective clients 110 that facilitates web searches on a search engine, such as search engine system 135. In this case, the toolbar may include software code that instructs a client 110 to send hypertext transfer protocol (HTTP) requests to server 120 for each web page that client 110 accesses. FE 310 may use the information in the HTTP request to identify the particular web page and web site associated with the web page that client 110 has accessed. Alternatively, FE 310 may receive similar data when clients 110 click on links provided by search engine system 135. In addition, the information received from clients 110 may enable FE 310 to identify other information associated with web site accesses, such as an amount of time a client 110 accesses a particular web page, whether client 110 scrolled through the particular web page, whether a purchase was made via the particular web page, etc.

I hope this helps.

(Google uses the toolbar data of visitor frequency to make this determination.)

Can you cite any sources on that one? Thanks.