pontifex - 3:18 pm on May 6, 2008 (gmt 0)

The whole mystery stays unsolved. We have changed pages on some domains. Some went grey, some not. On other domains we have not touched a bit and the pages show grey from former PR1 or white.

Since we do everything from super clean on some domains to shady on others, I can not assign a specific cause or pattern to the values nor to some rankings.

Here are some personal opinions:

a) First of all, I do believe that this PR update was partial. Google spidered a complete fresh index from end of January to the 21st of April and and went to rest (fresh bot only). All computing power was devoted to implement the fundamental ranking algorithms. Factors like the hilltop principles plus the trust rank ideas were applied as stronger factors and Pagerank re-calculations implemented. All links not set in March or links from smaller PR4 might have fallen through (=> only a feeling that something like that was going on)

b) Grey with ranking for search term:

Page content changed significantly or is passing links to the outside to fresh, unknown URLs

c) Grey and not ranking for search term in the top 1000 SERPS:

1. - if older than December 2007 : page is dead or has NO incoming links to mention

2. - if younger than Dec07 : hang in there!

d) Grey and former PR5+ : link seller, now dead

Just some theories...

P!