Hi Sean,
Here are my thoughts:
1) Which type of music is best for break-in (or does it matter)? Any music that uses a wide range of frequencies, any sort of rock, pop, blues. Avoid most vocal music, as they are tame. If you are breaking them in all at once, pop in a movie while you are out of the house and let it run continuous.
2) Do I need to break-in the sub/center/rears for the same amount of time (more/less/same)? Each model will break in differently. In your case, the rears and front L/R are the same model, so they will need roughly the same amount of break-in time. However, your surrounds are arriving a couple of months later, so you will notice a sound difference between them and the front when you first get them. The 532's can be enjoyable after a few hours of break-in (they will get better with more break-in). However, the 533-VAC sounds horrible out of the box, and you'll want at least 15-20 hours before judging it... for this one it might be better to play a more vocal type recording while you are out of the house. In my opinion, the sub will take the longest to break-in, but you can let it rip after 10 hours or so... but you will notice it getting better with time. Oh... this probably applies to any speaker, but especially the sub, let it warm up to room temp before testing it out. If it is cold where you live, the speaker could have been subjected out outside temps during shipping.... your speaker will be nice and stiff and unforgiving when it is cold.
3) How loud should the speakers be for break-in? They don't need to be loud, only audible. I would recommend against doing anything crazy with the volume until you get 5-10 hours under them.
4) How many hours before it is safe to crank the volume up a bit? 5-10 hours is safe, although you can crank-em earlier, they just won't sound as good until you get 30-50 under their belt... keep that in mind when listening. Depending on what you are upgrading from, they will probably sound better without the break-in 
The break-in process is nothing to stress about. Just be gentle for the first few days of listening and do not judge the speakers until you have had them running a couple of weeks.
-James