Not to jump in out of order, but I got mine today also. I am coming from a Galaxy S2 that is rooted and running 4.2.2 for a long time. Initial response is very positive. Phone is buttery smooth and fast. Very nice screen and I am very happy with the size and weight of the phone. I do not mind the home button as much as I thought I would. I am going to ATT tomorrow for a new SIM card as my S2 is not a micro card. I could cut this one down but I will keep it as a backup phone.
I will be rooting the S4 soon as I have the need to screw with everything electronic that I can. I could have saved a lot of money getting a subsidized phone from ATT, but my upgrade time is not up for several months. Lack of patience cost money sometimes.
Lived in Plano for many years, but retired to the lake. Don't miss the traffic, but do put a lot of miles on the car coming back to civilization for shopping and good golf courses.