Shean Donovan should be on the list. This guy has had a career high of 23 points until this year where he currently sits at 39 points, +11 and has 7 game winning goals. The season isn't over and he is hot right now with like 7 assists in his last 6 or so games. He is on pace to finish 2X or so more than his previous career high, playing basically third line duties. He also only plays 12.43 on average of minutes per game unlike many of the players listed above.
Martin Erat should get some consideration. He was a good rookie (33 points in 80 games) but then tanked last year (8 points in only 27 games). Since then, he has 43 points in 67 games and has been one of our most consistant players.
Walker, as mentioned, has had a nice year. People forget that Walker had 25 goals and 29 assists in 74 games in 2000. Injuries have really limited his effectiveness in the past two years. This year, he is fully healthy and has a nice complement of players with which to work. I don't think it's a stretch to say he's a legit 20 goal, 50 point guy.
Another guy is Kris Draper (atleast statiscally). I don't think he is any better, but his numbers sure are. Like Lehtinen last year, things are just finding the twine.
Mike Ribeiro - this was his make/break year - came through huge
Mikka Kipprusoff - Sutter is looking like a genius picking him up for a pick. Deserves serious Vezina consideration
Rick Nash - tied for league lead in goals at age 19 - who woulda thought?
Sheldon Souray could have walked away with this had it not been for injury
Honestly, I don't think guys like Recchi or Elias qualify for something like this. It's not like they completely sucked for years, and then all of a sudden started to put up huge numbers. They're just very good players recovering from bad seasons as opposed to bad players who have improved.
As a Sharks fan this question is an absolute NO BRAINER.
Watch some tapes of this kid skating last year, and then compare him to this year. It's absolutely amazing. Then look at his points and goals for this year. This kid has improved more in one year than any player I have ever seen in consecutive years in the NHL.
And if you didn't get a chance to watch Cheechoo skate last year, try to get a tape of his early games. Absolutely hilarious trying to figure out how a kid who could barely turn corners without losing his balance could find his way onto an NHL roster. This year there is no question that he belongs! And his skating is no longer a question mark.