I've played a few matches online and everything seemed fine. Was playing with Sonya and was able to land combos and parry with little issue. I was then assaulted by someone playing as SubZero. He was insanely good lol. I was on 7 out of 10 ranked :(

Maybe the Day 1 Patch fixes whatever online problems there are right now?

According to a few people, it didn't do jack for them. But that's not to say there won't be another patch soon after launch. In fact, I'm expecting there will be. I think they may just be waiting it out to see what needs stability once everyone has their hands on it.