Austin Longhorn wrote:
We need to move several large, established shrubs, including 8' crape
myrtles, several Indian hawthorn and a 6' ligustrum. The plan is to
move them in the late fall, when dormant.

I know I'll need to do at least some pruning, as the plants are too
large to move as-is... But should I prune fairly severely in this
situation to reduce their water needs, since I know they'll be losing
a lot of root mass?

Yes, but don't prune yet. Wait until you're ready to move them.
Right now you should root prune.
http://gardening.about.com/od/garden...ootPruning.htm
Then you may want to wait until spring to move them.

What are the odds I'll be able to keep each of these plants alive
after they're moved, given they're on the large side?

Pretty good if you do it right.