Announced on LoR's official Twitter account (link) today:
"We have been watching the meta since release of the new set, and some cards have proved to be... a bit too dominant. Later today we will be deploying a hotfix to adjust a few cards ahead of our scheduled January 5 balance patch."
Poppy - 3|3 > 2|3 (Level 2 - 4|4 > 3|4)
Gangplank - 5|5 > 5|4 (Level 2 - 6|6 > 6|5)
Yordle Explorer - Grant +1|+1 > Grant +1|+0
God-Willow Seedling - Countdown 2 > Countdown 3
Kinkou Wayfinder - Summons two 1-cost units > Summons two different 1-cost units
It's probably safe to say we're back at Day #1 of the Season as far as the Meta is concerned! =)