My in-store experience was great. Once I got into an Apple Store within less than 30 minutes I had activated the phone and had my first MobileMe sync done. The creative specialist I was talking to was eager to show me anything else I wanted, but there was a big line and I know what's what. Something I thought was interesting: the very first thing he did once I removed the plastic on the phone itself was to touch and sorta swipe at the screen. "No smudges!" he said with a smile on his face. When the 3G S was first announced we speculated about the oleoresistant surface, and it looks like that's a feature Apple wants to quietly promote.
I also tested the smudge-resistance on my admittedly greasy face and fingers (I once killed a Mighty Mouse within a month, if that's any indication). Sadly there's no official metric for resisting smudges, but on a 1-10 scale, with 10 being "smudges if you look at it" and 1 being "rub it on a pizza and it still squeaks" I would rate the new iPhone at a 5. The 1st-gen, which I had been using, I would rate at a 9. So there is an improvement. See the gallery for a little bit of testing.
How has your 3G S experience gone so far? Update #2: yes, this is the first iPhone I purchased. My previous iPhone was an aftermarket 1st-gen iPhone. So all of this is new to me, thanks for pointing that out.