So weird that you mentioned the petunia picklebottom backpack, I have been eyeing those for MONTHS now. If you watch babysteals.com they sometimes have them on there but sell out within minutes (which is why I've never snagged one).
I initially got a very plain and neutral (brown and orange) bag that I knew DH would hold and not freak out about. But for this baby I think I will get something pretty for me and DH can get over it, if we went out somewhere he normally carried the baby & I got the bag anyway.