For this year's medal, I'd vote for BK. Reason being that it is his last year, he's playing his absolute arse off, he's been an inspiration for an entire club and in two years here he's basically turned us from near wooden spooners, to premiership contenders.
The man is a God of a footy player at the moment, and this would be a great honour in his final year (you know, to go with his 2006 Premiership Medal, Clive Churchill medal and Dally M).