Google is set to make some changes in the ranking algorithm, Google Page Rank is one of the factors which makes a website appear in the search results. Higher the rank more chances of coming up in the google search, few Black Hat SEO gangsters are making use of this concept and are building links so that their site will appear in the top results of google search and with this they can easily do scams like Identity theft, Credit card etc. Obviously if google fails to do something about this then people will loose the trust on google so google has decided to make certain changes in both its search algorithm and Page Rank Algorithms so that these Black Hat seo will get caught.
Panda Labs reported that a malicious webpage for auto parts came first in multiple search with a number of keywords like (1984 nissan truck engine trouble shooting check list). This webpage was optimized in such a way that it will always stay in the top 10 results of google search.
This step of google is good as it will reduce the number of spammers and the malicious websites but still it will greatly affect the genuine SEOs as they have to study the new algorithm and then advise their clients for Page Rank. But still i must apperciate google for making such a good decision.
Google keeps on changing the algorithm very often but it is of no use always the security is been breached.