Evidently, the film must be something special, as filmmaker Dianne Whelan has already been commissioned to return to Everest next spring to shoot an 8-part reality series on the North Side of the mountain. The show is expected to air in December of 2012 and may be a replacement for the now defunct Everest: Beyond The Limit, which aired for three seasons on the Discovery Channel.
Below is the trailer for 40 Days, which looks very well done judging from this footage. Obviously they filmed this documentary on the South Side of Everest, which is considerably busier than the North these days. I'm sure they won't have any shortage of good stories to tell from the Tibetan side of the hill though.