Yuppers! I remember reading an interview with Toriyama ages ago in which he specifically said that Vegeta was intended to seem American. It was intended to clash with the Japanese style of the rest of the manga, making him seem 'alien' which is why a lot of Vegeta's attack names are spoken in English. I always assumed that Vegeta and the Briefs family in particular were supposed to be American.
Toriyama did the character designs for GT and said he changed Vegeta's hair because a lot of fans said Vegeta would never change his hair. Talk about a spit in the eye there!
As for how I feel about Chatwin - I like him! I can see how a lot of people would expect an asian to be cast, but as someone else said earlier in the thread, I always imagined him to be Caucasian, possibly because I was younger when I watched this and didn't shed a lot of thought on his ethnicity despite how it does have a lot of Japanese influence.
My biggest annoyance over Chatwin is that in the pictures of the movie set, he appears to still have brown hair. They're surely not going to give Goku brown hair? It just doesn't look like him!! Hopefully it's just a trial run or something.
Seriously cannot wait for the trailer.