encyclo - 11:12 am on Apr 6, 2006 (gmt 0)

The difference between St Patrick's day and Tartan Day is that the former is celebrated by people and the latter created by governments. This is not to deny the importance of Scottish influence in North America, simply that the event doesn't have the profile. If there was enough spontaneous popular acclaim for Tartan Day, perhaps Google might notice. As it is, Tartan Day has a long way to go.

I'm surprised that Google doesn't recognize St Andrews Day on Google UK at least.

Disclaimer, I'm a Sassenach ;)