All the contenders (Sabathia, Price, Hernandez) pitched tonight, and they were all superb. A good case can be made for each of them to win the award, and it could end up being quite close. A lot of people have been making the case for Felix Hernandez, and for good reason. He leads the AL in ERA, IP and SO. He is also on a terrible team that doesn't score any runs (Mariners are last in runs scored by a mile), so he's only 13-12.
Normally, 13 wins would not be enough for a starting pitcher to be considered for the Cy Young Award nor would being only 1 game over .500 be good enough. It's not like there isn't anyone else to consider: CC Sabathia (21-7, 3.18) and David Price (19-6, 2.73) have had great seasons, and so have Jon Lester and Clay Buchholz.
King Felix has had an unbelievable season and might have 25 wins if he were on the Yankees or Rays, so the desire to give him the award even though he has 13 wins is understandable. There is one interesting stat to consider in evaluating King Felix: he has given up far more runs that Sabathia or Price that are not earned. If you just look at their RA (not ERA), Price and Hernandez aren't that far apart.
Should that matter? I mean, they're unearned runs for a reason. Every situation is different, but sometimes pitchers can get away with some bad pitching because of the ERA rules.
One case is from August 15th, when Hernandez allowed 6 runs to the Indians, all unearned. He got the first 2 outs, then his defense committed an error, and he gave up 6 runs in the blink of an eye, capped by a grand slam from Travis Hafner. Hernandez did get the loss, but his ERA was helped by 6.2 "scoreless" innings.
Didn't Sabathia and Price also have unearned runs? Yes, but they combined for 16 (8 apiece), while Hernandez had 17 on his own. It (like his W-L record) is probably the result of playing on a crummy team that commits a lot of errors, but that always plays a role in these decisions. It's not clear whether Sabathia or Price will pitch again in the regular season, but they both finish strong enough to be legitimate Cy Young contenders.
One wild card in this is that Hernandez will probably start in the final game of the season, while the other two might not. He could pick up another win, pitch a shutout (imagine a no-hitter!), take a loss or have his worst game of the season. I find it a little hard to believe that he'll win the Cy Young award with only 13 wins when Sabathia has 21, but a shutout on the final day of the season to bring him to 14-12 with a 2.20 ERA might be enough.