The only way you might be unaware that today -- October 21, 2015 -- is the date that Marty McFly and Doc Brown time-travel to in "Back to the Future II" is if you literally go out of your way to avoid anything remotely related to pop culture. Hell, even "Good Morning, America" had an extended piece on it this morning, complete with a Delorean and life preserver vest.
Thing is, some of us (read: tremendous dorks) have been looking forward to this day for years. We are the ones who, when someone posted photoshopped images of the time interface from the Delorean in years past, claiming that whatever day was shown in the altered image was THE day, immediately left scathing comments about the poster's genetic makeup.