The weight of the passenger makes a huge difference in my experience...

 

You'll be fine.
Just take it easy.

Here is a pic someone showed me of a chic that didn't have any gear on and went down.
Scars are cool for guys, but girls hate 'em.

My wife always suits up if she's on the back of my bike.

[IMG]local://upfiles/7167/98F99423762742AB884203FA46A728EF.jpg[/IMG]

 

+1 on that. The upside is you'll have those nice big jublies on your back... kinda makes up for it.

The main thing is that they don't move around a lot at a stand still or really slow speeds. Readjusting their position or something similar isn't such a big deal once you get going.

 

+100...the most important thing imo she can do or not do

 

for the getting your nuts crushed when you stop part i just told my girl the first time she rode with me to push back a little on the pegs with her legs and it keeps her from sliding in to me.

 

Had my first passenger last week. Like everyone else said, not much difference, have her look over your shoulder during turns and push on the tank during stops. The thing I noticed was my wrists hurt when we were done, other than that it is was fun.