Norris Hopper, 28
Minors: 3,617 PA, .290/.345/.337, 190/252 SB, 4 years in AA or higher
Majors: 45 PA, .359/.435/.462
PECOTA 2007 Weighted Mean Projection: .270/.312/.313, -10.4 VORP, 1.6 WARP
Chris Denorfia, 27
Minors: 2,257 PA, .296/.377/.441, 80/110 SB, 2.5 years in AA or higher
Majors: 161 PA, .278/.358/.382
PECOTA 2007 Weighted Mean Projection: .296/.365/.459, 22.9 VORP, 3.8 WARP
I'll let you come to your own conclusions, but people smarter than me think Denorfia should be an above average major league CF offensively in 2007. His minor league track record supports it and he was very good at the end of 2006 when he got regular playing time. He was voted the best defensive OF in AAA.
Norris Hopper had 45 PA with a BABIP of .389. A small sample size in which he was lucky. He has 1 HR in 45 PA in the majors -- 3 in 3,600 PA in the minors. Nothing besides a miniscule sample of major league at bats suggests he's anything other than a Tony Womack like offensive player without the speed of Womack in his prime.