It's not much data and it's not particularly meaningful, but I have the data and I finally had time to figure out how to use it, and here it is. I'll go through the hitters one by one. Remember that all of this data is from April, so the averages are only based on 40-50 batted balls from quite a while ago. And realize that the data's inherently skewed-- for the average batted ball "stat", you're better off striking out than hitting a weak grounder to short. And bunting will lower the average as well, including sacrifice bunts. So take it all for what it is worth.
Jason Kendall Average batted ball velocity: 72.49. Maximum velocity: 95.55.
Without context right now, these numbers don't mean much to anyone. These numbers show that Kendall does not hit the ball very hard. Most hitters managed to hit at least one ball harder than 100 mph, and Kendall failed to do so.
Prince Fielder Average batted ball velocity: 86.29. Maximum velocity: 109.69.
Looking through his list of balls in play, it confirms with what I've observed-- Fielder crushes a lot of balls really hard. He didn't absolutely demolish one in April-- we'll get to that later-- but he hit 14/46 balls harder than 100 miles per hour. His average is a bit low compared to some others because he has quite a few balls in the 40s and 50s, and a couple even in the 30s.
Rickie Weeks Average batted ball velocity: 86.3. Maximum velocity: 116.84.
All that stuff about bat speed and quick wrists was definitely ju stified in April. That ball hit at 116 mph (off of Carlos Zambrano) was the 12th hardest in the majors in April and the hardest hit ball by a Brewer. Such exciting potential.
Bill Hall Average batted ball velocity: 81.73. Maximum velocity: 106.3.
Billy does have the ability to really connect with one, but he doesn't do it often. 5/45 were hit harder than 100 mph. At least this does confirm that he does have the ability to hit the ball very hard, even if his average is pretty low because of a lot of grounders and pop-ups in the 50s and 60s.
J.J. Hardy Average batted ball velocity: 88.84. Maximum velocity: 113.67.
This might be the most encouraging thing I find in the data. Hardy struggled in April and still was second among the starters in velocity and hit the second-hardest ball on the team in April. That pretty much confirms he was getting unlucky then, and he's gotten unlucky now. He hits the ball very hard, and balls just haven't fallen for him this year.
Ryan Braun Average batted ball velocity: 82.5. Maximum velocity: 109.98.
Don't read too much in to the fact that Braun's average is lower than most of the others. 12 out of the 55 he put in play were better than 100 mph. Braun hits the ball hard.
Mike Cameron Average batted ball velocity: 90.08. Maximum velocity: 107.8.
And here's your team leader from April in average batted ball velocity. When Cameron connects, he seems to hit them all hard-- just none really, really hard. And he strikes out enough that you know he squares it up when he hits it. Cam has very few balls hit in the 40s, 50s, and 60s; he makes consistent contact.
Corey Hart Average batted ball velocity: 86.29. Maximum velocity: 105.5.
Hart seems to be a guy that just never really crushes a ball, but he does consistently hit them hard. Maybe it's just his swing, which seems to not be as long or fast as most other hitters. Regardless, he comes in with a nice average, and he too doesn't hit many balls very slowly. It is possible to hit hard grounders, and Hart does it pretty well.
That's all I have for now. Hopefully we can get some data from the past few months and do some more in-depth studies. It is fun to look at for now, of course.