I just did about 6 different searches of the forums (unlimited timeframe) and was able to find all of one (1) thread about iPhones being lost in delivery. (And even that one was unverified, so I'm assuming the OP would've ranted and raved a lot more had they not received it.)
You're better off ordering from Apple or AT&T.com as soon as pre-orders are made available to get your iPhone ASAP. Heck, some have even been delivered early in the past
I don't know if your friend wants a commission or is just ignorant, but if you wait until the day it goes in sale, you're risking waiting in long lines and/or not getting the exact model or color you prefer b/c they're already out of stock; it just depends on where you live.