Just wondering, the one thing I hated about SR, is that it was basically over after 10 mins if you are down several kills and towers, cuz the enemy gets the entire jungle, gets every dragon, and has more items than you.

There are too many factors involved to say.

For the most part yes there is snowballing. How severe? Depends on a lot of different variables.

How is it compared to SR?

The snowballing on this map can potentially be worse than on SR due to the alters alone. If one team locks in the first two alters when the open and then farms well while they are up it's pretty much GG even without kills just on the bonus gold alone. Even then the bonuses to AD and AP the alters give will further help you keep them locked and with the map being as small as it is you pretty much control the rest of the game.

Now you can come back but it is a lot harder than on SR.

Simple answer: yes it is worse than SR in its current state.

I agree with Nick. It's easier to snowball hard, but it depends on how good of an advantage you get.
I've seen people come back from 10, 15 kills behind.. even more on SR.
Here, 10 to 15 kills ahead means something is going wrong with your team's play style.
Also, there's simply 2 less people on each team, so there's less variance each teamfight than SR.

I like the space by the wraiths, it provides more area to juke haha

i honestly hve had more comebacks in tt than in summonner's rift, i wouldn't say that snowballing is rare, because it's more common than in summonners but ciomebacksa re also possible, i managed to win a game against a 16/0 kha'zix by the sheer power of altegame ryze, and yesterday we ahd a fed enemy, cho gath and nidalee, we were sined, fiddles and Irelia, fiddles started securing spiders by himself and irelia kept farming, eventually we could win teamfights, and finally won the game, and eys that happenend just yesterday, then we happenned to stumble into a Darius/jax/rumble team and got roflstomped..., so both factors are possible, and be sure to run something to counter Darius, he's on a tier of his own in tt.