http://www.wikipedia.com announced yesterday that they are now going to implement no-follow tags on all outgoing links in an attempt to curb link spam. They push enough PR that sneaking a link into their pages would likely be enough to get you out of the Google sandbox.

I'd expect a number of user-submitted content sites to quickly follow suit.

I've added rel="nofollow" to some of the links on my site, but yet Google, Yahoo and MSN do visit those links, even when no other link is pointing to them.

Infact Google even follows a link that's been blocked by robots.txt, as long as there's a link - even if it is written in Javascript! like <a href="javascript:function('URL')"

I was reading in Business Week that Wikipedia's founder is building a search engine that is supposed to be a Google killer. For those of you who may not know the name it's Wikisaria - this search engine's aim is to use people power to rank search result pages rather than rank them with algorithms.

The founder of Wikipedia said it is going to take about 3 years from now to finish that search engine.

I'm looking forward to it!

Google already organizes their results based on user behavior. That's why they appear to be so good at combatting spam results. In actuality, they see that users click on the result and then quickly back out to the results page again. That's an indicator to them that it wasn't a good result.

That also explains why all those Javascript redirect spam pages are sometimes successful. They are hijacking the browser away to another page and you can't hit that back button. Google doesn't see you back out, so they assume you got a good result.

It's also rumored that they loosely mine the data from their toolbar to estimate a site's worthiness for keywords.

Yeah, I suspected that they measure the bounce rate for a page/ site.

Breaking the back button with JS is possible, but it's considered to be an user annoyance. I think MSDN has the back button disabled. A few browser savvy users will still be able to go back by clicking on the little down arrow on the top left that takes you back to anywhere in your browser history, unless the site decides to disable the browser address bar.

Users mostly leave if they find a page/site to be spammy but also leave if they can't find the content above the fold, or if the page takes too long to load or if the page didn't have the stuff they were looking for, but that doesn't mean the page is bad, it just means that it was meant for a different audience.

Google discloses that by enabling the PageRank bar, one's browsing history or pattern is sent back to Google. So, I think they use it to measure the quality of a site.

But now, if one installs a StumbleUpon browser toolbar, they can easily see a websites' rating listed next to the site in Google, Yahoo, MSN based on the thumbs up given by stumblers.

2 pages on my site got 5 stars, the rest didn't get any I'm guessing that must be because those pages had too many ads, but they do have substantial content also.

I think the rule of thumb is to differ the ads, until a page becomes popular and then add the ads, to make up for hosting costs and bandwidth cost of a popular page.

This is something that surely had to happen eventually, because this is one of the "reasons" people choose to edit on wikipedia, so they can add their links. Taking away that reason should help improve quality.

Improve quality I guess but if you are giving a real edit worth something of value I don't get why it is unfair to get something back for your work. I haven't done it myself (because I am too lazy mostly) but if somebody is going to really work and help them build their project why is it wrong?

I somewhat agree with Sarah's statement.

I feel that Wikipedia is a gigantic resource filled with useful information, and sometimes in a few cases it can be a competition for certain websites.

If an article is written somewhere else and it totally relates to what's on Wikipedia then I don't see why they would want to not give credit for that article by passing in pagerank.

It is also very discouraging for websites to be just shut-off by Wikipedia and DMOZ when search engines give so much importance to them. But, I guess they claim to perhaps improve the quality of the internet by not including certain sites in their directory/ related links section.