We're definately not as strong as we used to be without Neural Parasite and players, including pros are changing their builds and unit compositions. We see Roach/Hydra/Corruptor coming out of constant top pros in recent tournaments.
I'll add to each Race as players respond and give appropriate counters feedback.
Terran
Protoss
Ex. Early Warp Prism Drops - Add a Hydralisk Den @ 7-8 minutes after scouting a robo. Post #2
Zerg
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Basically, state what your new effective counter or technique is in whatever situation or unit comp you've faced and an explanation right below that. I'll add it to the list and put your post # next to it.
Remember it can be a tactic you use, a unit composition you find working well, or a build order for specific units @ different times which help defend.
It can also be a specific move you make on a specific map in order to counter for ex. a Terran Hellion/Marine drop.