Here's a video showing the extent of what happened this summer:

[link|http://nsidc.org/news/press/2007_seaiceminimum/images/20070917animation.mov|http://nsidc.org/new...0917animation.mov]

so if you get the player from Apple, you should be able to watch it.

The short version; about a quarter of the perennial ice cap (that's the part that stays solid all year every year) melted.