Dominion has EVERYTHING we've been asking for in the past months. And ALL the champions are good and viable in Dominion, here's why:
Gold gains are much more consistent throughout the game and NOT only based on CS.
-NO 0 CS support metagame (seriously, that alone should be enough for Dominion to be regarded as amazing)
-NO "laning phase" and everything that comes with it (lasthitting, roaming, ganking, jungling, etc.), many people like it but doing it all the time can get boring.
-"lategame" and heavy item-dependent champions (most ad champions) can get their expensive items much earlier and be a threat throughout the whole game, and not just in its later phase.
Map size much smaller compared to other maps
-global abilities (Ashe, Ezreal, Lux, Twisted Fate, Pantheon) much more effective.
-more fast-paced gameplay (you don't need to walk over 1min to reach the zone of fight).
Small teamfights-oriented map as opposed to 5v5 teamfights
-Most "alternate" champion builds that were considered "non-viable" in competitive play are now much more viable because of the absence of big AoE-oriented teamfights (and also because of laning phase). Ex.: AP Nunu, AP Shaco.
All amazing reasons to play Dominion!
@Veigar and Nasus whiners: GOLD GAINS ARE MORE CONSISTENT AND NOT ONLY BASED ON CS. Champions that need a lot of farming are still viable.