You got it exactly
Your assumptions and the example are all correct!
Both ways have advantages and disadvantages. The getter/setter approach for example allows you to define bean properties for which there doens't even have to be a real class member, i.e. getters which return "calculated" values. On the other hand the field access approach doesn't force you to publich all class members just for the sake of a persistence provider.
I don't know if this will change with
Java EE 6 / JPA 2 but it sometimes was annoying for me that you can't mix both ways to specify persistence properties on a per-property basis. It's either field access or getter access.
Marco