For me, smartpost and surepost stuff comes within two days, but traditional UPS is coming much slower. I want to blame it on the weather, but the smart/sure post stuff is unaffected so it seems to be something more than that. I've ordered a lot of stuff from Amazon this Christmas and receive a new package almost daily (dang those daily deals, lol). I have one package I ordered last weekend, was schedule to arrive last Tuesday and I still haven't seen it. I got an email yesterday from Amazon that my package would be late (duh) but when reviewing the tracking the estimated delivery date has never updated so I really have no clue when I should expect to receive it. Unfortunately it had a gift I need this week and thought I had ordered in time to receive, so I hope it makes it's way to me soon!
Also, I've done prime for years now and this is the first year I've noticed lags in deliveries...