There are many rumors about today’s Google Balls logo, but we know it is not birthday related. Google in the past have celebrated their birthday on September 7th but not anymore. Danny has good history on Google’s Birthday over here.
Google celebrated their 11th birthday on the 27th, the 10th also, 9th, 8th but the 7th and 6th birthday logos were on the 7th.
This year, you can expect the 12th birthday logo to be live on the 27th