Buck is our starting LF in 2008 barring disaster, but the other three are far away.  Mitchell won't see the majors until September 2009 at the earliest, Sulentic is defensively questionable as an OF and may switch positions, and probably will not see the majors until 2010 or 2011.  Herrera is a wild card.  He is tools wise very similar to Bradley, and could move quickly if he is healthy and clicks.  If Buck is at LF in 2008, and Herrera appears ready to take over RF in 2009, maybe Bradley in CF after Kotsay departs?  

whatever happened to Jeremy Brown? Maybe he's not here because he's on the 40 or something, but how do Brown & Suzuki compare?

Herrera has the ability to be an impact prospect.  Buck has a chance to be a Cano kind of guy who is better in the majors than scouts thought if he can keep his batting average up and develop HR power to go with the doubles.  Buck really reminds me a lot of Luis Gonzalez without the fluky (roids-driven??) home run seasons.  Barton has a chance to be an impact player if he can develop 20-30 home run power and hit over .300 consistently in the majors, and he is still young enough to do so.  Italiano has a very high ceiling, but his injury and bad mechanics make him a bust candidate.  The rest of the crew besides Mitchell and Sulentic are lower impact guys that can be valuable non-star major leaguers.

After spring training:Much like the major league roster. Players are cut from major league roster and begin to fill out minor league teams, you also have invited players that must be placed. I hope that helps.

Dan Meyer's specific problem was shoulder impingement, for which he finally had surgery in 2006 after non-surgical remedies apparently didn't work.  Impingement is caused when the rotator cuff rubs against a protuding bone on the shoulder blade called the acromion.  People have three basic shapes of acromion, and impingement is a constant risk for a person with a hook-shaped acromion (I am cursed with one of these and spend a great deal of time avoiding muscular imbalances and so far have avoided surgery.)  I have never been able to find out whether Meyer has a hook-shaped acromion, but if he did the surgery likely would have shaved down the bone.

Shoulder impingement is exacerbated by muscular imbalances, like so many other injuries.  If Meyer is able to correct the muscular imbalances and his rotator cuff has healed, his chances for recovery should be good.  Shoulder injuries involving the labrum are close to a death sentence for pitchers, but Meyer didn't have any problem with his labrum that I've heard.  Rotator cuff surgeries have a much greater success rate than labrum repair surgeries, but not as good as the success rate enjoyed by Tommy John patients.

Meyer's velocity was down from Spring Training 2005 and never recovered pre-surgery.  This is too be expected with someone who is suffering from impingement.  As you can imagine, having your rotator cuff scraping on bone during a throw tends to impact performance.  I have not heard how Meyer is doing, but if he has his velocity back in Spring Training he becomes an intriguing guy again.  Meyer was one of the best left-handed prospects in the game prior to his injury, and he still has a chance to be very important to the A's.