Shelby Miller is generally regarded as one of the best pitching prospects in the minors. Tehran probably gets the nod over him, but you could make a strong argument for him being number 2. He hasn't had much high-level experience, so mid 2012 is probably the ETA unless something unusual happens.
Goldschmidt, entering the season, was a fringe top-10 D-Backs prospect. Didn't make fangraphs' top 10, BP rated him as a 2 star prospect, BA put him outside the top 10, Sickles put him at 9, etc. Here's the scoop: He's got significant hitting skills, the main one being his power, as we're seeing right now. The knocks on him are twofold: one, he's got zero defensive value. He's got the range of a lawn ornament, so corner OF is out. He's only adequate at 1B, and the offensive bar for that position is very high. Two, he's got a long swing, and his 26% K rate in the California League points to contact and OBP problems in the future. If he keeps hitting like he's hitting, he could move up lists. One other thing to note is his platoon split - he did most of his damage against lefties last year. Also he put up big numbers in the Cal League which inflates offense like crazy. However, he's still hitting this year and he could very well keep it up - don't underrate his power. My gut, when I look at him, says "Right handed power bench bat," but there's certainly the potential for more. I could see him having a career trajectory in the Chris Davis/Brandon Wood mold, but like I said, there's potential for more.