I expect people to start whining about Roy Harper's effect again being "broken" as before, and to be honest, really, with Overload being banned, Rama being errata'ed, it looks like they forgot all about the fact that people really think Roy Harper's effect is cheap and "broken" as well. And with Overload banned... it'll be just that much more rampant in Teen Titan decks.
I don't see a major
Shift in the meta happening, if anything I see the meta staying about the same from pre-PCNY. Granted CS and TT won't be running Overload anymore, but that doesn't mean the decks aren't that good. I spent the night in bed while I was trying to get to sleep thinking of all the possible cards I could bring back and throw in my CS deck now since I can take the Overloads out and some of the possibilities are just to die for.
TT never really needed Overload to live anyways, it was the SNO combo that everyone hated in the CS deck, a combo that wasn't even the backbone of the deck, just a small combo that just "worked" in the deck. I expect CS to still be around as well as TT making a huge return, and of course, all those other off-curve builds like New School, etc. who can now not worry about an Overload hitting their own character... Geez... this limits the only way of beating the Xavier's School deck by just running Have A Blast! or Foiled... it used to be that you could Overload your 4 drop (for instance, people would double Beatdown their Mark V in a CS deck and Overload him), and you had to do your 4 drop because the Xavier's Dream deck would have Total Anarchy up just to stop the card from gaining a counter...
I expect that deck to make a great come back as well... Gamma Doom looks good again, pretty much everything looks good again.