According to this image from the Dominion website, its gone from flash stacking on Summoner's Rift, to ghost stacking in Dominion.
How come no one took rally/heal/revive?
I'm glad its gone from flash+X, but this doesn't seem much better.

It's an example screenshot. It might not represent the summoner's skills that real players will pick when dominion comes out.

in dominion there isn't exactly the concept of "laning" and towers are not static entities to be destroyed once and strolled past for the rest of the game.

flash is god on TT and summoner's rift because there are tons of walls and being able to move a short distance instantly is very beneficial (into or out of tower range for example)

It makes sense that an extended movespeed buff would be stronger than a longer CD short-range teleport on a (presumably) smaller map with far less jungle than in Summoner's Rift. Getting to capture points faster will be useful for defense and offense, whereas a short-range teleport will be less useful given the location and nature of Dominion.

It's mostly because there are fewer walls that you can jump over with flash, thus having a speed boost is much more viable.

Also the "my side" "your side" is not quite as extreme... yes full health champs do respawn on opposite ends and being near there should tend to be safer, but there is more free roam and fewer safe spots, so flash might not get you far enough to get out... but I imagine it is still quite usefull.