Chris Young is currently ranked 35th on ESPN's Player Rater and 43rd on Yahoo!'s rankings. Young should be kept for his 30/30 potential (currently 25/27) but be aware of his low batting average potential, as well (only a .241 career average).
For those of you that like to gamble a little bit with your keeper selections, OF Justin Upton poses a bit of risk. Currently ranked 96th on ESPN and 102nd on Yahoo!, most would call this a down year for a player that had a 2010 ADP of 18.6. No one would blame you for keeping his .273/73/17/69/17 line and 30/30 potential on your roster for 2011 but a lingering shoulder issue has him all but shut down for the rest of the 2010 season. Depending on when your keepers are locked in, you may have to make this decision before more is known about this injury.
If you are looking for a keeper based on position scarcity, C Miguel Montero has the potential to be a top-7 catcher. In 78 games this season (he missed 57 due to a severe knee injury), Montero has managed to hit .271 with 9 HR, 43 RBI and 35 Runs. Doubling up those numbers to simulate an entire season and his 18 HR, 86 RBI and 70 Runs puts him in the upper tiers of catchers and is right in line with his 162 game averages.
Are there any other players on the Diamondbacks roster you'd be willing to use a keeper selection on for the 2011 season? If so, open up the discussion by leaving me a comment.