An Arctic Ozone 'Hole' - a new threat?

I was looking at the news today and came across a very short article from the Independent, which, despite it's size, had been the sixth 'most-read' Environmental article in the Independent during 2011. I'm not sure whether it's the topic that drew the most readers, or the title: 'GIANT ozone HOLE found above Arctic' (own capitalisation!). Due to this likely exaggeration and the fact that I hadn't heard this apparently popular news story, I decided to have a look at the original paper the article was based on. The paper was published in Nature as is titled 'Unprecidented Arctic Ozone Loss in 2011' by Manney et al 2011.* They reported a record low ozone level of 220-230 Dobson Units (DU) recorded in March 2011, but could you day this was a 'huge hole'? Also, was this anything to do with climate change or this just a random and freak occurrence?

Polar Stratospheric Clouds (PSCs) photographed in Sweden
http://earthobservatory.nasa.gov/IOTD/view.php?id=622

According to the authors, the possibility of significant ozone 'holes' in the Arctic has been debated for decades, with some arguing that higher temperatures in the Arctic than the Antarctic prevented such formations. The basic