Well, I won't recognize that one either.
"Real" date time group is year:month:day:hr:min:sec. So, Pi day would be in 3145:9:2:9:20:xxxx. Translated to 'American' that would be Sept 2, 3145 at 9:20 in the morning. Not in my lifetime. But, that's just a function of the Roman calendar and is probably not related to the earth at all :)
Of course we could go by the Mayan calender and the earth would cease to exist :)
But, I will be out riding tomorrow morning, even if it isn't the real Pi day. :D