Every year, the first 10 games or so are filled with results that seem intuitively screwy (Colorado, anyone?). Sometimes, the new stuff is a sign of real change, and sometimes it's just an artifact of chance and small sample size. Here's some of the things I think are telling and others that will fade with time.
Don't Buy it -
The Colorado Avalanche
The Avs are looking real good right now, but it isn't going to last. They have a terrible shot differential, a 935 SV% and a team SH% of about 14. Both percentages are unsustainable (although I think Anderson is the real deal) and once one or both fall back down to earth, the Avs will too. They're roster is really, really young to boot and will probably hit a wall half way through the season. Best in NW right now, perhaps, but my bet is they still finish last.
Atlanta Thrashers
Another lesser light overachieving, the Thrashers shot differential is even worse than the Avs. Their success has a lot to do with a league best 37.5% PP success rate which will inevitably regress.
Toronto Maple Leafs
As fun as it is to laugh at Toronto and Brian Burke, there's little chance the Leafs are actually this bad. They've suffered through the worst goaltending in the league and currently have a 6% shooting rate. It's a perfect storm of terrible afflicting TOR right now and it's bound to end eventually. If Gustavsson returns and can at least be average, the SH% should correct itself to some degree and the Leafs will start winning some games.
Calgary Flames
Calgary's off to a "good" start, but the truth is they've allowed the most shots against in the league, have a shot differential well in the red and their money forwards have been abysmal in just about every aspect of the game. Notable performances by depth players, the 4th liners and a sky-high PP percentage (34.8) has allowed them to outscore their issues, but that won't last forever. Unless Sutter get's the team in the black in terms of outshooting, things are going to get ugly here in town very soon.
Edmonton Oilers
Same deal as above, except it's ES SH% that is driving the Oilers bus. Their shot differential is similarly bad, but they've currently scored the most 5on5 goals in the league (22), despite only generating some 23 shots a game. Hemsky's hurt now too. Not going to continue.
Buy it -
Boston Bruins
Most writers in this corner of the web could have called the Bruins decline. not only did they lose a number of decent players this summer (Ward, Kessel, Yelle), much of their success last year was derived from out of this world percentages. The regression was inevitable, which is why I picked them to be a middling club in the EC this season.
Detroit Red Wings
Losing Hudler, Hossa and Samuelsson isn't easily overcome. On top of that, sticking with Osgood in net and backing him with a rookie is probably a mistake. Adding Bertuzzi and losing Franzen for 4 months can't help but further hurt the Red Wings at ES. Zetterberg, Datsuk and Lidstrom are great so they won't tumble too far, but their relative early season struggles look like the real deal - the NHL's best outshooting team the last few years has a SD of just +1.4/game thus far.
Phoenix Coyotes
I know. I can't believe it either. I've seen the Coyotes play a couple of times this year and they look...good. It's a foreign feeling. They are currently 5th in the league in terms of SA/G (26.7) and they have a positive shot differential. Tippett is the real deal and the club actually has some strength down the middle in Hanzal, Lombardi, Lang and Mueller. Doan is, of course, excellent while Michalek and Sauer are underrated, good value players. Bryzgalov and Labarbera are a good bet to prove better than average goaltending as well. I doubt they'll continue to lead their division much longer, but be prepared for them not to suck for the remainder of the year.