Pages Coming In & Out of the Google.com Results & Google Index

Earlier today, I briefly noted that Google is dropping pages and then bringing those pages back into the Google index. The question is what is going on. Honestly, I have no idea. But at least, let me give you a ton of forum threads that may have some clues as to this weird Google behavior.

WebmasterWorld Forum Threads:

• Very Odd - Big Drops in SERPS Today April 26, 06
• Major Change in Supplemental Result Handling
• Somethings Up Right Now! -- 30 domains just went "home page only"
• Pages Dropping Out of Big Daddy Index

There are also other threads, but those are the most active and recent on the topic at WebmasterWorld.

DigitalPoint Forums:

• Is Google cleaning their index?
• supplementals was improving, now right back where we started?