Considering a case could be made he shouldn't have been there last year because he should have been in freaking prison or at least serving his house arrest or whatever, I can't say I feel any sympathy.
If anything, I applaud the NSF for playing hardball rather than bending over backwards and letting the prima donnas dictate the terms of the sport to them like the ÖSV did with Fenninger. Of course, it's easier to do so when you already have a glut of the strongest people in the sport (it's not like the Norwegians don't have enough athletes capable of victory in Petter's absence with Sundby, Røthe, Krogh, Brandsdal, Tønseth, Golberg, Gløersen, Hattestad and Dyrhaug), and of course a lot of victories will come with an unspoken asterisk (or a spoken one for the more outspoken of Petter's fans) because of the absence of one of the biggest stars in the sport. But no athlete is bigger than the sport, and since Northug has, rightly or wrongly, come to embody a lot of what is wrong with the sport (eg proliferation of sprints, conservative racing of distance events), and is a rather unlikable character away from that, it's hard to see that his being absent will be that bad a thing for the sport.