I like your hitters, pretty good balance there. Your starting pitchers have some weak spots, though. Owings didn't pitch well last year, and now he's in the major's preeminent bandbox. Buehrle and Carmona are decent (IF Carmona can return to form), but each is a low-k pitcher, which will hurt you in roto (=rotisserie...close) leagues, where there's typically an innings/starts limit. Halladay, Volstad, Cueto are all good picks, and I like Escobar as an injury sleeper.
I'm not saying drop them immediately, but you shouldn't be too hesitant to drop Griffey, Overbay, and Guzman when there's an intriguing player on the wire.