My opinios after a few days of testing with 5 wows, on 1 pc:

1) Do the wasd keys go to both characters, or does one character follow the other?
I use KeyClone, and you can set keys not to be broadcasted. I'm used to navigate with my mount but I also use my AWSD keys and Q & E.
Don't broadcast them = done :wink:

2) Can I use the mouse in mouse look mode? I tend to run with both left and right buttons held down.
Why would you like to look around on your other chars ? Not needed imo, just macro all their spells and yer done. Set your other chars to follow you and then run your main window / character with both mouse buttons pressed.
I fixed this by giving eac box char this macro:
/target Wnote(name of my main char)
/follow
Then just put it under a hotkey( I used F) and the will follow you as soon as you press F..
That's all