I jailbroke my iPhone 3G when it was running 2.0.1 and it worked fine. Ever since then I have packed my iPhone with apps and music. I just need a few thoings answered before I attempt an upgrade.

1). are there any App store apps or Cyda/Installer apps that could interfere with the upgrade process?

2). I have the hack that allows me to drag and drop hacked app store apps into iTunes and thus I can sync these apps to my iPhone? Was this hack patched in 2.1 or can I just us the same process I used on 2.0.1?

3). Are there any apps thus far that are not compatible with 2.1?

4). Is there anything special I have to do to ensure that I don't lose my carrier signal?

5). Is there anyway I can make backups of all my apps so I can restore them really fast?

6). Will the upgrade to iTunes 8 complicate the upgrade/jail breaking in any way?

thansk in advanced.