Faceoff wins are interesting in that they're the most over-rated under-rated statistic. I can't count how many times I've watched a hockey game and heard the commentator say how faceoffs are so critical but underappreciated. Given that virtually every colour guy in the league says that same line, I don't see how they can be underappreciated.
However, there is definitely some value there. While hockey isn't really a possession-driven game (or else the dump-and-chase tactic would never be used), its definitely better to start with possession of the puck. In critical situations (i.e. less than a minute left, third period) that faceoff win can mean the difference between a win and a loss.
The other thing about faceoffs is that they're typically won by veteran players. There are all sorts of ways to cheat at faceoffs, all sorts of sneaky little tricks, and generally the veterans have these down better than the youngsters. Take the Oilers' list, for example:
Jarret Stoll - 677/1229 - 55.08%
Dustin Penner - 104/189 - 55.02%
Marty Reasoner - 478/906 - 52.75%
Kyle Brodziak - 153/297 - 51.51%
Shawn Horcoff - 487/963 - 50.57%
Marc Pouliot - 21/44 - 47.72%
Sam Gagner - 125/299 - 41.80%
Andrew Cogliano - 215/542 - 39.48%
The only rookie on the right side of 50% is Kyle Brodziak, which, given his age and minor pro experience, probably isn't surprising. The Oilers under MacTavish have traditionally been a strong face-off team (particularly the 05-06 squad), so I have no doubt that guys like Gagner and Cogliano will eventually improve.
Unfortunately, we don't have statistical tools at our disposal to show us won/lost battles along the boards, and all of the small plays that occur in a game other than our eyes. I'm rather convinced that, if we did, we would see veteran players as a whole running roughshod over the rookies, even quality ones like the two guys at the bottom of the Oilers' faceoff list.
Finally, one real surprise to me- how effective Dustin Penner has been on faceoffs. I was a little skeptical when I saw MacTavish using him in that role on the powerplay (I haven't been a fan of converting wingers to the middle since MacT tried it with Smyth), but he's been an excellent faceoff man. I suppose it makes sense, given his size and strength, though.