Last week, everyone was talking about the PageRank sculpting change within Google. First off, the SEO definition of PageRank sculpting is basically telling the search engines which pages of your site to value more over others, by adding in nofollow tags (among other things) on pages that are of lesser value. Using nofollow tags will tell Google not to transfer any high PageRank from one page to another page. With this tactic, Google and the other search engines will pay more attention and assign more PageRank (value) to those pages you have put more value on, and less attention on other pages which have lesser value.
The purpose of doing this is to get those pages you deem higher in value to rank higher in the search engines. The higher your PageRank is for a particular page, in theory the higher that page should rank in the search engines.
Apparently, some have debated how well this practice works, or if it works at all.. Regardless, last week at SMX Advanced, according to Search Engine Land, Matt Cutts said that PageRank sculpting no longer works to help flow more PageRank to the more valuable pages of your site. , This means if you have a great PageRank on your homepage, adding in nofollow tags or using other methods of blocking less valuable pages on your site no longer helps give other pages any more PageRank.
Here is a before and after analogy that Search Engine Land uses to help explain the situation:
Before: Imagine authority is money, and a particular page has $10 in “authority” to spend. It links out to 10 pages, so each of those pages gets $1 ($10 divided by 10). If it links to 20 pages, each gets 50 cents ($10 divided by 20). If it links to 5 pages, each page gets $2.
After: if you have $10 in authority to spend on those ten links, and you block 5 of them, the other 5 aren’t going to get $2 each. They’re still getting $1. It’s just that the other $5 you thought you were saving is now going to waste.
Search Engine Land goes onto say that if you have used the PageRank sculpting strategy in the past, not to panic and remove your nofollow tags. Google will not be penalizing anyone using this strategy anytime soon according to Matt Cutts.
My advice, until all of this gets situated and Google figures out exactly what they’re doing, work on other SEO strategies like link building, writing new content, etc. over doing any further PageRank sculpting.