indyank - 12:43 pm on Nov 15, 2011 (gmt 0)
Refining official page detection: We try hard to give our users the most relevant and authoritative results. With this change, we adjusted how we attempt to determine which pages are official. This will tend to rank official websites even higher in our ranking.
This is clearly a ranking change, but I'm not sure if I understand this correctly.
They have asked their quality testers to rate pages as "vital", if they are the official pages. This is well explained in the guideline doc.
For example, if a user searches for Windows 7, the official pages will be from Microsoft and they have adjusted their algo to always return a set of relevant pages from Microsoft's domain or sub-domain on top, for "Windows 7".