Well, we did Busch Gardens and the family had a lot of fun.
I called ahead to ask about their firearms policy, specfically, carrying open or concealed within the park, and got a bit of a run-around. The gal who answered the phone didn't really know the answer, but that didn't stop her from telling me what she
thinks the answer should be. Final answer I got (3rd person I talked to) was that they did not allow weapons or knives in the park. I asked if it was posted somewhere at the entrance, and was told "yes" but they couldn't, for certain, tell me where.
I looked as diligently as I could, but I could not find a sign on the way in. As wally mentioned, they do search bags on the way in. As I saw no sign, I really wondered what they were looking for.

They did not have any kind of metal detectors or wands, so I suppose that one could easily get through while carrying on his person.
On the way out, I looked again for signs, and
I did finally find it. It was a big (8'x3' or so) sign that you passed as you walked from the parking lot into the park. The sign was pretty busy, lots of stuff on it. And I suppose that there were people between me and the sign as we passed it. Although it was a good sized sign, it was easy to miss/ignore. At the very bottom it said something like "The following are prohibited: weapons, knives, etc., etc..." It rounded up stating that they'll ask you to leave if you break the rules.
So there you have it.
Parry