The only thing I have to say about Braun and being "proven" is that he has done ALL that he can (and I mean all) to prove that what he is doing now is no fluke. Believe me, I would like to see it over a much longer time period, but check out the Cube's stats on this kid: http://www.thebaseballcube.com/players/B/Ryan-Braun-1.shtml
He was a highly touted prep prospect out of Granada Hills who did not go in the first round because he said there was virtually "no shot" he would sign; he wanted to live the college experience. As a freshman in arguably the toughest baseball conference in the country, he put up an 1.100 OPS with 17 jacks and 36 XBH (!!!) in 242 ABs. As a 19 year old kid, playing against the best players in the country, he did THAT! I know he was 19 and was using metal, but that is ridiculous. He battled thru an injury-plagued sophomore season (and still posted a 1.045 OPS) and then BEASTED the ACC his junior year, becoming the ACC PoTY (1.197 OPS, .726 SLG, 23 SB, 18 HR, 36 XBH, 219 ABs). Okay, great, that'll earn you a top five draft pick. Just for comparison, if he was a junior LAST season, he would have been the EASY #1 prospect in the draft.
He signed pretty early and got 10 games in at the rookie level and 37 in at A-ball, not shocking because he was supposed to be a polished college bat. Well... in 193 ABs between the two levels, he only hit .352 with 10 homers and 31 XBH. That's a homer every 19.3 ABs for those who struggle with math, which is a pretty unheard of number for a kid who had just switched to wood from aluminum in the middle of a season. He also K'd 40 times, a pretty high number, but nothing too alarming, but only walked 11 times. Oh, and his XBH % was only 45.6%.
In his first full season in '06, at Brevard County (A+), Braun struggled slightly to begin the season. Some may be attributed to the fact that the FSL is a slight pitcher's league and that BC plays for the pitchers, but he still managed 21 XBH in 227 ABs, 7 homers, 14 steals. This would prove to be Braun's toughest task, but the Brewer's saw through his "marginal" numbers at A+ and promoted him to AA Huntsville where he just took off and has not looked back since. A quick run-down: 35 XBH (including 15 HR) in 231 ABs, 21 BB, 46 Ks, 12 SB, .303 AVG. For a 22 year old in his first full-season at AA, that's a pretty damn good line. And then, as we all know, he took AAA by storm to start 2007, to the tune of .342/.418/.701/1.119 in 117 ABs, and that includes 10 homers, 22 XBH, a 55% XBH rate (insane), and a 15:11 BB:K ratio.
My point of this lengthy statistical run-down of Braun's career: Sure, it'd be nice if we had a year-and-a-half of Braun in the Majors to make this decision, but he has done everything in his power to prove that what he is doing now is 100% legit. He has not stopped hitting since he arrived at U of Miami in 2003 and there's very little that suggests he's going to stop at some point soon. The kid is a great hitter, and though his approach could use SOME work, he's still doing a good job of selecting a good pitch that he knows he can drive and actually driving it. If you're ever going to take a risk with a guy, Braun has, at the very least, validated taking a risk on him.