Did someone say "Oh god where is Graven to explain in great detail with his unfathomable Dominion knowledge what the new patch means for Dominion!"?
I honestly played very few twitch games, 3 or 4, and I can't be truly unbiased yet. The changes are meant to make him a better straight-up AD carry in SR, but fights in SR and Dom differ wildly - first off, there are no full-on teamfights in Dominion, not fighting is often the better chance, unless you can guarantee an unfair fight, letting the enemies escape is not a bad thing, since the fights are for territory control, no wards and so on.
What this means is, I counted Old Twitch as the best Dominion carry, because he was a great provider of information - Oracles is avoidable and there are no pink wards, so it's easy to spot the enemy team and hover around them without being detected. Information is the most important thing in LoL, but even more in Dominion, since there are no wards and no ways to know exactly where the enemies are apart from a few champion abilities.
This also allowed Twitch to pick and choose his fights to a great extent, not to mention making him a great tool for helping and controling bot, focusing on the point of attacking and positioning, negating the enemy carries/squishies because he could afford to stay in stealth for as long as he wanted.
New twitch's stealth is 8 second at most. This is less than rank 1 ambush before. What this means is Twitch can no longer afford to stay in the jungle stealthed and just pick off stragglers, or scout for his team. His is now "tactical stealth", also known as "awww, isn't it cute ^_^" or "omg what is this overpowered bs" depending on the champion who has it.
Let's explore that for a second.
- Wukong. Has dash. Leaves clone, allows for juking abilities and unstealthed jukes in brush.
- Talon. Has dash, silence and slow.
- Vayne. Has short-range dash, has cc.
- Akali. Has dash, incredible burst.
- Teemo. Has mushrooms and a blind.
- Shaco. Haha.
Now Twitch is the only ranged character apart from Vayne and Teemo who has access to stealth. He also has a slow, too, which is now targetted. The problem is all the other tactical stealth characters can use their stealth as a last-ditch escape effort. You're Vayne and you're being chased in the jungle? Pop that ult and juke around the next corner! You're Talon and there's several nasty peoples incoming? Pop that ult and wing it! You're Shaco? Haha.
Twitch uses his as an engage, and to escape from battles if given the chance (i.e. unattacked), but never for an instant "oh god help me right now" button. He couldn't before, true, but it was a much better engage ability simply due to the duration. Now it's used more as a very short-time initiation and steroid.
Neotwitch is in all honesty a better AD carry than Old Twitch. I haven't run the numbers, but he does more damage, stacks poison easier, and his expunge now scales with AD, not to mention actually has an ult now.
What he isn't is the best Dominion carry. I have yet to play a few more games with him, but he fills a much more traditional AD carry role now, instead of old scout/assassin/carry Twitch, which by default places him behind the Vayne/Kog'maw AD carry union.
What's that? Noone said what I assumed at start? Oh...ehm...oh.
edit : Oh yeah, Xin's ballistic missile build seems incredibly OP now since I literally haven't seen a Xin feed post-15 minutes, and I literally haven't seen an Eve do anything but feed. Take that for what you will!