Galllardo, of the Milwuakee Brewers, is one of the best pitching prospects in baseball. He is getting called up in place of Chris Capuano (hurt) today. He isn't necessarily going to be a starter immediately, although that is certainly the eventual destination for him.
According to the 07 prospect handbook, Gallardo has a fastball that sits at 90-94. He has a very good curveball, best in the Brewers minor leagues. He also has an 85-89 mph slider, which according to the handbook has become a plus pitch. He also has an improving changeup. He changes arm slots to keep hitters off balance, but he has repeats his delivery very easily.
In 2006, Gallardo allowed just 6 home runs in 155 innings (split between High A and AA). In his minor league career through 06, he has posted a 19-9 record, a 2.38 ERA, 329 strikeouts in 303 innings, and has only allowed 230 hits and 110 walks, good for a 1.12 WHIP.
This season, Gallardo has gone 8-3 in 77 2/3 IP, allowing 4 home runs, striking out 110 and walking 28, which in all is good for a 2.90 ERA and a 1.04 WHIP. This year most of his numbers have risen, except for his walk rate. I also got this one from RotoAuthority: he has a .293 BABIP (Batting average on balls in play). This shows that his great numbers in his career have not been luck, but just pure talent.
Before the season, Baseball Prospectus predicted a 3.92 ERA and a 1.35 WHIP in the majors in 2007 (their projections always assume the player is in the majors, even if they are in A ball). They also compare him to some very good current pitchers: Peavy, Harden, Kazmir, Penny, Zumaya and C. Zambrano.
Gallardo is a can't miss prospect. As previously stated, he won't be immediately inserted into the rotation. However if he pitches as expected, it shouldn't be long before he is thrown into the same discussion as the aforementioned young guns. Watch out for this kid, he's a good one.