For those of you waiting eagerly for the next big thing (or the Galaxy S4), AT&T has just sent me an e-mail that customers who’ve pre-ordered their S4 will be receiving them promptly on 25th.
Of course, you will also be able pick one up at any official AT&T retail store also starting the 27th but be early as there will be a limited supply. (I suggest show up when the store opens if you want to guarantee yourself one.)
As for other carriers, T-Mobile will also be starting online sale on the 24th (meaning you will have to wait for couple days for shipping) while Sprint is officially selling the Galaxy S4 starting 27th in its stores.
Verizon? Well, you will have to wait a bit longer, approximately 1-2 months due to a number of bloatware/locked bootloaders they are working on. Oh well, you will eventually get an S4 or you can change carriers.