At a younger age, Wieters has more power, more walks, and fewer strikeouts than Piazza. It's not even close. Wieters is a very complete and very balanced hitter, and to take the comparisons one step further, here are some of his offensive comparables.
Some very impressive comparables, even with Travis Lee included (I have no idea what happened with Lee. His stats at the beginning of his career were pretty good, but he never advanced much and kind of trailed off after about the age of 24 or 25). Berkman and Teixeira have both consistently hit 30 to 40 home runs with career batting averages around .300. They also have maintained an OPS in the .900 to 1.050 range, and usually collect around 100 to 110 RBIs per season. Those numbers are very similar to the stats that Mike Piazza put up during his career, and well above just about every other catcher who played the game. And if you compare those numbers to current star catchers like Joe Mauer and Brian McCann, it makes them look a bit pedestrian.
Before we go any farther with this, let's make it clear that Wieters is not guaranteed anything in his career. While guys like Teixeira and Berkman have done very well, we have to keep in mind that guys like Travis Lee never really panned out. While I think that the odds of Wieters performing along the same lines as Lee are not that high, it's still a possibility, so we have to keep it in mind until Wieters reaches his full potential. Now that we have that out of the way, what can we expect from Wieters in 2009?
If Wieters becomes the Orioles starting catcher at any point in the season, he'll be 23 years old during his rookie season. We have major league level stats for Mark Teixeira to use in our projection, but Berkman didn't see any significant playing time until he was 24 years old, so we'll have to do some retro-projecting for this analysis.
Using the numbers above, we can deduce that since Berkman's numbers at 24 were similar to Teixeira's numbers at 24, then Berkman's numbers at 23 would have been quite comparable to Teixeira's numbers at 23. In the minors, Berkman had power numbers that were a bit inferior to Teixeira's power stats, and his home run rate was a bit behind Teixeira's during his rookie year, so we'll say that over approximately 600 plate appearances, as a 23 year old in the majors Berkman would have hit somewhere in the neighborhood of .270, with 22 or 23 home runs, and an OPS between .800 and .815. Those numbers aren't exactly based off of a rigorous scientific analysis, but we're looking for basic ballpark figures here, so they'll work.
Now, if Wieters has demonstrated similar power numbers to Berkman in the minors, then we would expect somewhere between 20 and 25 home runs from him in 2009 were he given a full 600 plate appearances with the Orioles. I'm fairly optimistic about Wieters, so I'll go with 25 home runs. As for batting average, Wieters hit .365 at AA in 2008, compared to .306 by Berkman at AA, and .316 by Teixeira at AA. That means we can tack on at least 25 points beyond what Teixeira hit at 23 with the Rangers to Wieters' major league projection, which gives us something like a .285 to .295 average on the low side. On the high side, we could add 40 or 50 points and project an average of .320 or so. I'll take somewhere in between, and say that Wieters will hit .305. We'll also throw an additional 60 points onto Teixeira's OPS, which gives us something around .870. In the Orioles line-up, that should be good for somewhere around 80 RBI if he hits in the middle of the order.
So, to summarize, I think the following numbers are fairly reasonable for Wieters in 2009 (all stats based off of 600 plate appearances):
TPC 2009 Projection for Matt Wieters: .305 average, 25 home runs, .870 OPS, 80 RBI
Those numbers are very similar to what Evan Longoria posted last year, so the A.L. R.O.Y award is certainly not out of the question for Wieters. However, if he only gets 400 or so at bats with the Orioles, he might only hit 15 to 18 home runs, which might not be enough for Rookie of the Year if someone like Taylor Teagarden comes up and hits 30 home runs with a .280 batting average (which I think he very well may do).
Anyways, that's what I've got for Wieters. I could be completely wrong on him, but I'm about 80% sure that he'll turn out exactly the way I think he will. We'll come back and look at these projections in a few months and see how things look.