Brian McCann's 2009 was famously marred by a Lasik surgery that didn't take. One can't help but think that the drop-off from his 2008 level of production had something do with this (.281/.346/.486 in '09, .301/.371/.523 in '08).
The decline in McCann's rate statistics coincided with declines in his base skills (-1 BB%, -4 contact %, -2 flyball %). Still, the drop-off was marginal and to be expected following a season as mammoth as McCann's 2008 - but even so, McCann was still one of the elite catchers in 2009.
Going into his age 26 season and with another offseason Lasik procedure (that will hopefully go much more smoothly), I'd put expectations for McCann somewhere between 2008 and 2009. That's a conclusion with which the industry's leading prognosticators seem agree:
Ron Shandler's Baseball Forecaster: .286/.350/.509
The Bill James Handbook: .291/.362/.511
Assuming he's healthy, Brian McCann's is one of the most stable skill sets in the game. And that has to give comfort to Frank Wren and fantasy owners alike.