[Brian]

Heh, I didn't phrase that well at all - it will sync once it comes to the foreground and sees that it's been an hour since the last sync. I'll go edit the last post.

AFAIK, OmniFocus can't access the network in the background - so yes, if you want to be sure that your sync made it to the server, you'll want to let it complete and then switch to another app.