You should know by now they only change their logo on internationally celebrated/recognized days
St. Patrick's Day is neither internationally celebrated nor recognized. Kind of goes against your theory, doesn't it?
Veterans' Day, aka Armistice Day, is celebrated in France and the UK.
Happy Halloween - October 31, 2005
Celebrating Google's 7th Birthday - September 2005
Anniversary of Lunar Landing - July 20, 2005
Independence Day - July 4, 2005
Happy Father's Day - June 19, 2005
Frank Lloyd Wright's Birthday - June 8, 2005
Mother's Day - May 8, 2005
National Teacher Day - May 3, 2005
Earth Day - April 22, 2005
Leonardo da Vinci's Birthday - April 15, 2005
National Library Week - April 10, 2005
Google celebrates Vincent van Gogh's Birthday - March 30, 2005
World Water Day - March 22, 2005
Happy St. Patrick's Day - March 17, 2005
International Women's Day - March 8, 2005
Happy Valentine's Day - February 14, 2005
Chinese New Year - February 9, 2005
Happy New Year! - January 1, 2005
Would you be so kind as to tell me which of these are the INTERNATIONALLY celebrated holidays???