We just had a huge fight over this issue on another forum that I don't want to replicate here. But Beyonce... no. She doesn't look the part, she's not tall enough, and she doesn't have the acting talent for it either. Disagree if you wish, but I also don't think that the part should be reimagined to have WW be a black woman.
Wonder Woman needs to be played by someone tall, strong of body and spirit, and someone that can kick some serious ass believably on camera. Furthermore, she needs to be able to come off as not silly looking in the costume, handle a rope well, and do a lot of under-stated BDSM stuff without being too overt or campy. Now, we probably won't get someone that fits ALL of those catagories, but we should get one that that fits most of them, AND looks the part. If appearance, and thus race, were unimportant, then I'd suggest Gina Torres for WW - she's only 5'10 and I'd prefer at least 6'0, but she has the talent and attitude to pull off the role if she looked the part. Unfortuneately, she doesn't look the part. Wonder Woman's appearance is well fixed in people's minds, and changing it to something entirely different for the move to the big screen I don't think will go over well, nor do I think that it should be done.
I don't want to get involved in another big flame war over this though, so I probably won't participate much in this thread.