Front and Center, by Catherine Gilbert Murdock

The best thing about (finally) reading the third book of a trilogy, especially the kind of trilogy that is actually three books and not just three volumes of the same book, is that it finally gives you a chance to sit back and figure out what the trilogy was about, and what it achieved.

Some spoilers for the first two books follow!

The series by Catherine Gilbert Murdock (which I am assuming stops at 3, wahh, though a quick Google search has left me none the wiser on this score) is about...