Got mine wednesday, I originally went in the store with the intention of buying the note 2. However when my fiance saw the s4 she instanly fell in love. One credit check letter we walked out the tmobile store s4 in tow.
First impressions are generally good. Huuuuuge fan of the screen, being a long time samoled hater because of the yellow/blueish hue. Im proud to say this screen has none. Its bright, its beautiful, and 1080p movies look gorgeous. Color accuracy is greatly improved over the gs3 also.
Battery life seems pretty good so far, further analysis is needed. I've been on it pretty much constantly, which is the reason I've had to charge it quite often. That said it's been off the charger for about 7 1/2 hours and it's at 43% , thats with heavy use.