1. Troy Tulowitzki - Every other year, Tulo gets 600 PA. When he gets those 600 PA, he puts up 30 homers, 90+ RBI, double digit steals, and the good average he has every season. While this would be one of those years he gets 600 PA, with his storied injury history, you just can't be sure with Tulo.
2. Jose Reyes - Reyes did play a full season last year with 700 plate appearances, but the last time he did that before last season, it was 2008. The AL might keep Reyes more healthy, but don't bet your auction funds or an early pick on it.
3. Hanley Ramirez - Hanley has had 600+ PA every season but one of his career, so you can count on him being in the lineup, but his declining defensive abilities may soon make a move to 3B a necessity, and he's not hit for a solid average the last two seasons. There's risk that won't come back, but the home runs and steals should be comfortable at the 20/20 range.
4. Starlin Castro - Castro is only in his age 23 season, so he may just blow up, but he's had some odd issues on and off the field, and he's really not taken that next step in three years so far. That said, he's a 10-15 homer, 20-25 steal guy with solid average, so he's nothing to sneeze at either.
5. Elvis Andrus - A lot of guys were disappointed in Andrus last season. In real baseball, Andrus is better than the 5th best shortstop, but last season he only put up 20 steals, and with his contact and lineup, folks expect 90+ runs and 30+ steals, especially with his lack of power. I wouldn't overspend, but if you go in expecting a guy who won't give you power and build your team around that, he'll be an excellent piece.
6. Derek Jeter - He won't give you 15 steals or homers anymore, but he seems to always be double digits both and hits for a solid average. He's been overrated for years, but now that expectations have come down to a 15/15 level, he's much better valued.
7. Asdrubel Cabrera - Cabrera exploded in 2011, and folks didn't know what to expect of him in 2012. After essentially lower version of the 2011 season in 2012, fantasy players have a better idea what to expect now as Cabrera enters his prime. He has 20ish homer power and double digit steal speed. He'll also give you solid average and is just entering his age 27 season.
8. Alexei Ramirez - Okay, I'll admit to being biased for Ramirez, but he's in a similar spot as others around him. He'll give you 15/15 with solid, but not great average. The worry I do have is his walk rate dropping drastically from a career ~6% to under 3% last season. He's entering his age 31 season, so he could be starting on his way down, so he's one not to overspend for this year.
9. Jimmy Rollins - He may not give you a high average, but he's got solid power/steals. He put up a 20/30 line last season, but he scored 100+ runs for only the second time in the last five years, and the lineup around him is aging quickly, as is Rollings. At 34, the speed could drop off quickly, so be wary.
10. Ian Desmond - Desmond did have a great 2012, but there are some worries as his HR/FB was nearly TRIPLE his career number before 2012. I wouldn't expect 25 home runs out of him, but around 10 home runs and 20 steals is probably to be expected.
Unlisted, underrated: Alcides Escobar - Escobar has been building to his 2012 for 3 years. I would expect solid speed and a .280+ type of hitter. He could be akin to Elvis Andrus with a lesser lineup around him possibly, so he may not have the same runs/RBI numbers as Andrus, but he should be similar in production.
Unlisted, overrated: Yunel Escobar - There was a point where he was expected to turn into a 15-20 homer hitter with good, not great speed. Nothing has ever come of that. I wouldn't even expect double digits in either homers or steals with Yunel, and he's also coming off plenty of off field issues in 2012. The one redeeming thing to me that would even make me consider Yunel is that the Rays generally don't take a risk like this unless they are pretty sure it will turn out well.
Position strategy - This position doesn't have the elite talent that it once had, but there is plenty of depth. Tulowitzki's injury history and the inconsistent performance of Reyes and Ramirez make the top of the list just less overall elite. That said, there's plenty of solid starting shortstops all the way down to 15-17. So, just understand that SS is a position you won't likely get elite production from and you'll be fine. There's no reason to drop $25-30 on a shortstop or a first 4 round pick on the position either.