Seriously, no words can describe how excited I am for this and this is just the first trailer. GTA5 is set in San Andreas, an easy favorite when it comes to GTA cities. That alone should get your sandbox boner raging.
Hot damn, I really hope that all the footage shown was actual gameplay cause if it it than that is a huge HUGE step-up from GTA4. Seriously, I am having a really hard time trying to express my excitement right now. Just watch it and see for yourself.