I watched the first episode of the Bleach dub last night, and I have to say, its much better than I expected. Karin was done the best, in fact she was done very well. The hollow that attacks the Kurosaki clinic and the little dead girl, both throw away characters, were unbelieveably better in the Japanese version, but characters who will be developed eventually were done well.
I can't say anything concrete until I see Byakuya (I have suspicions that Orihime will be butchered, but what're you going to do?), but the Bleach dub of the first episode is the exception to the rule: "dubs suck".