Are you more concerned about the written part or the practical test climb?
The written (multiple choice) exam is kind of CA lite. I believe I recognized a couple of questions as repeats from my CA exam. Read the questions carefully so you don't get caught out on tricky wording, and it's not too hard at all.
The tree ID samples on my exam were all pictures, very nice clear photography, 4 or 5 shots of different aspects of each tree, so if you know your trees, the ID key is there somewhere.
The practical climb was easy. An easy throwball shot, couple of TIP advancements to a pre-marked height, then both limb-walks to the work stations were straightforward. One limb-walk I could have maybe used a redirect, but not required. We had 30 minutes to do the whole climb, I was done in under 10, and I was being very deliberate with every move.
I think one key to the practical is keeping a commentary going for the examiners, so they have no question about you're being on top of things. "OK, I'm doing my pre-climb inspection now, no electrical hazards present, no visible defects, there is some deadwood there and there, but nothing that looks like it will present a hazard...blah, blah, blah." I had two examiners, I actually requested one please put on his hardhat as he would be in my workzone, don't know if that was a "test" or not, but there you go.
All in all, pretty basic. Don't drop your handsaw, and good luck!
Northwind