As well as writing this blog ( I like writing) I also nick on to Wikipedia and write articles about subculture on there. I just did this on World Goth Day, and spoke to Martin OldGoth (my buddy Rachael suggested I speak to him) who was one of the two founders. He was awfully nice, despite still recovering from Wave Gothic Treffen, and answered a few questions for me.
Anyways, I thought I would replicate it here. You can read it on Wikipedia as well:
May 22 is World Goth Day  The Official World Goth Day site defines it as "a day where the goth scene gets to celebrate its own being, and an opportunity to make its presence known to the rest of the world" 
World Goth Day originated in the UK in 2009. BBC Radio 6 was looking at a number of music subcultures. Goth DJs Cruel Britannia and Martin OldGoth got an event up and running. It was decided that May 22 would be the day when this event would be held regularly. 
The tradition continued and spread outside the UK, with a website being initiated to coordinate and advertise events worldwide.
World Goth Day celebrates the sub cultural aspects of the Goth subculture. Aspects of the culture like fashion, music and art are celebrated by fashion shows, art exhibitions and music performance. Many of the events feature local Goth bands, and some have taken on a charity aspect with events in the UK and Australia supporting favoured charities like the UK Sophie Lancaster Foundation, a charity that tries to curb prejudice and hatred against subcultures. 
The event has evolved to be now celebrated by goths all around the world, including the UK, the US, Australia, Singapore abd South Africa.