Wayne, Good choice on bringing the 'blad. I have a century graphic for my MF 'travel' camera, because the lenses are cheap and interchangeable with my 4x5. I carry 2 backs, one for color and one for B&W. (I just got an Rb and I like how the backs fit my century)
Anyway, 'blads dont focus close like our RB's do, so make sure to bring either an extention tube or a +1 filter. I would also reccomend a monopod.
Oh, I dont know where you stand on film, but I've been into fast color film lately. Take a roll of fuji 800 NPZ and try it for street shots.