I resurrected my iPhone 3G, sold my iPhone 4 ahead of the rush, so will be reacquainting myself with an old friend while I wait for delivery of my 6. Working a charm so far :)
I'm going to hold off for a bit. The 5 is working fine for me. I need a minivan before a new phone...and, crazy enough, they initial costs are getting to be equivalent on those two things! The 128 GB 6+ is like >$1k unlocked. Crazy. My 5 is unlocked too...which is nice.