Glad Asurion is taking care of you on the phone and upgrading you to a much better phone.
As far as your questions:
FIRST THING:
If you have a 32GB micro sd you're planning on using you might want to get the switch made right away. Once you setup your Arrive with the current 16GB you will need to setup everything again on a new install. Google for some tutorials. It's not too difficult to do. Just need a jewelers screwdriver set.
1. I have a 2003 Exchange server but I don't use the certs. I just put in the server credentials and everything syncs up (almost
) pretty good. You'll have to do some checking and experimenting. Try to get this account setup and working so it can be your main e-mail/contacts. When I first set mine up I just put in my Live credentials. Then when I redid everything with the 32GB the 2nd time around I made sure to get Exchange going first.
A couple of errors I've had with Exchange Activesync is that on an appointment if I put in a note on the appointment on the phone it hasn't synced to Outlook. I don't understand it either. It's been a little inconvenient with how I have ran on Windows Mobile for all these years. Never a sync problem with it that I remember. Maybe a later Exchange brings better results or the Mango update. All of the phone number fields aren't seen on the Exchange contact either even though the phone number is there in the phone so you can't edit it out/in. A couple of appointments I put on the phone didn't show up in Outlook and I was late to them because I saw them at the last minute on my phone. Oh well, a few things still need to be worked out but overall it's pretty good.
2. Your Exchange & Live contacts will merge/show together in your phone. If you have two of the same contacts it will link them together. Your Live contacts can't see what's on your Exchange. It's pretty sweet and I thought at first I would hate it. I haven't messed with a lot of editing contacts to check what gets modified and where though. Even after suggestions to on this forum to uncheck the contacts mine doesn't show that option in the e-mail settings. Mine says "Content to sync - Email" and that's it under Windows Live. Like I said it isn't a big issue really. They're combined on the phone but separate from which servers they reside.
3. I don't use Facebook so I have
NO IDEA how it works in WP7. My wife uses it on her EVO and likes it real well.
After a few days you'll get used to the OS and you'll marvel at how fast and intuitive it is. You'll wonder how you lived with the TP2 for so long