Have a look at the paradox I explained on Matt Cutts blog: http://www.mattcutts.com/blog/quick-comment-on-nofollow/#comment-243379

Google should make its own way to discriminate what is spam and what is not and not rely on nofollow that immediately has been abused by webmasters so much that now the same Matt Cutts came out with another page on his blog saying that webmaster should not abuse nofollow, an that they should let PR flow, and blah, blah: http://www.mattcutts.com/blog/pagerank-sculpting/

So before we should use nofollow, now we should let PR flow. That really sounds weird! It sound like Google algorithm is getting either overloaded and not bale to follow all links and assign the proper PR that’s why PR is not so important anymore (according to Matt Cutts) that we should let it flow.
The funny part is that Matt Cutts blog itself is packed with nofollow links, even many smart comments form smart authors still get a nofollow link.

Keep in mind a few things.

1. PageRank is one of many factors now that Google uses to position a URL in their search results. Google has stated they have HUNDREDS of factors that they now use. Don’t get too hung up on ‘PageRank’. Know that other factors exist such as Google Toolbar data, clickthrough data from the search results, previous searcher activity (did they click on that domain before, do they typically look for ‘Golf’ the sport or ‘Golf’ the car, etc.).

2. Google is very good at launching things and making a big to-do about them when they launch and then change something later without making any mention of it. Just because that is the way nofollow worked in 2005 doesn’t mean that is the way it works today. Personally, I feel it’s pretty close to the way it works today but I have some pretty strong evidence that Tweets from large twitter accounts still have an impact on SEO.

3. Just because you may not get a benefit directly from Facebook or Twitter doesn’t mean you don’t get a secondary benefit. I did a post about this on my own blog (well, really just a Posterous, shorter more random thoughts). Tweets get fed via API to lots of locations on the web. Blogs, websites, etc. When that is done, the links are ‘followed’ links and thus an advantage is had at that time (it is also why ‘good’ spammers are still pounding the twitter stream with links).

4. People on Twitter and Facebook are early adopters (well, less so now than a year ago, but . . . ). They are well connected on the internet in comparison to others. When they see your tweet, they are more likely to link to it from their own blogs, websites, professional sites, etc.

5. Lastly, pulling PageRank directly from Twitter.com (with a HIGH number of links and overall domain PageRank) would really screw up the algorithm and be really beneficial for spammers. Keep in mind, I used to be a spammer. I’d setup 35 profiles online and drop links on newsgroups, forums, blogs, etc. I even went further than that and I figured out how to automate Amazon’s So You’d Like to . . . and Amazon’s Listmania lists . . . later learned how to automate product reviews. All of those things REALLY helped me to do well in the search results for the products I sold. Removing the significant advantage spammers have (to your point) makes it less worth a spammer’s time invested to figure out how to crack the code. As for Facebook . . . I work in the Search Engine Optimization industry. Make it possible to gain significant PageRank advantages by setting up a fan or profile page that has 50,000 fans or friends and . . . the SEO industry will figure out how to exploit it.

There is a TON of money in getting to the top of Google. How much? Do a search in Google for ‘Google Keyword Research Tool’ (while logged out) and click on the first result. Then type in a fairly common word. Export the data to CSV and open it in Excel. Do the math between the traffic volume for the different terms and the ‘cost per click’ to pay for a top position in Google AdWords for that term. You will see it is often times hundreds of thousands of dollars per month. Do a search for a 3Ps term (porn, poker, pills) and that skyrockets even further.

This stuff makes the livelihood of many people and organizations possible. Not just the spammers. But the legit SEOs (like I have become sense 2005), the legit advertising firms, legit marketing departments, and the people that support them from the janitor to the CEO.

Again, great post . . .

Brent D. Payne
SEO Director, Tribune Company