A minor correction - arctic sea ice isn't at its lowest ever for this time of year - we'll see how it goes over the summer though.

Definitive data here :

http://nsidc.org/arcticseaicenews/

Hi Big Gav
I wasn't only referring to the extent of sea ice. A crucial factor is that ice that has formed since last September over open water is young and thin; and therefore is much more likely to melt this northern summer.

Source: http://environment.newscientist.com