But there are still cookie cutter teams in Gen V. Volt turn shells with Tyranitar and terrakion, rain offense, rain stall, sun offense, sun stall, baton pass with espeon...
It was already said before, but I'll just have to restate that this gen showed us that we can't prepare for everything. We give up way too much by running specific counters for top tier threats rather than simply running amazing utility Pokemon or sweepers who can take out your opponent's team before you lose your own. Checks are popularized to the point of having a higher precedence than counters. Scizor is ran because he checks plenty of Pokemon (terrakion being the most important one) and still has many uses aside from doing just that. Golurk counters terrakion...but what else can he do in OU that makes him shine? A few things, but hardly enough to justify a team slot unless your strategy demands it.
I'm also going to outright say this here. Gen V has made more players carefully think about their turns than any of the previous gens did before. I am not saying that players did not think about making careful plays in previous gens. I am simply saying that Gen V makes us consider it more and is causes us to make decent predictions instead of random guesses.
Gen IV scenario: "Oh man, I have my choice scarf heatran out. I can outspeed his gyarados and go with hp electric...BUT WAIT! My opponent may just happen to have a heatran on his team as well, so shouldn't I go with earth power? What do I do..."
You either use earth power as your opponent switches in heatran, who was everywhere, and then you credit yourself for your great predictions skills. Or you use earth power against gyarados and your opponent questions your skill because you made a guess about something your opponent never had on his team to begin with.
Team preview eliminates these random guesses and by already letting you know what you should be looking for, allowing you to build your strategy from there.
I think alphatron has made a great point here.
I didn't play much competitively in gen 4 OU and have dabbled in gen 5 OU while focusing mostly on RU.
As RU has no seemingly direct comparison to gen 4 metagames, it can be hard to have a strong comparison perspective. However, I've mostly stuck to RU because some of my favorites are a little more competitive and the general lack of weather.
I've noticed the following:
Weather! it was pretty much Sandstream before, which just helped undermine the opponent's bulk slightly... now weather wars are a constant extra aspect to prepare for
Team Preview. This affects every tier and is honestly my least favorite change from DPP. I prided myself on surprise pokemon and sets which could be more easily worked around if the opponent knew/could intelligently guess what was coming. This is now much harder to pull off, although admittedly I appreciate the ease of prediction from a defensive perspective.
Eviolite. This really makes a difference in RU because there are more things that can use it and some of the most potent defensive threats are actually eviolite users. Not a huge change of the metagame per say, but I like the additional diversity.
Volt-Turn abuse. U-turn was very important for scouting, now it's mostly for offensive pressure and to gain momentum (not to mention somewhat annoying). Not that u-turn wasn't effective and widely used back in DPP, but I think it is far more widely abused now.
Power (and speed creep) pretty self explanatory here.
-As alphatron described, I often had immense satisfaction by predicting a switch to a pokemon that I didn't even know the opponent had (much like the Earth power Heatran scenario). While still nice, I don't enjoy nailing the (known) predicted Gligar switch with ice beam, for example, quite as much...
And hard counters aren't always as important because team preview can help avoid the situation when you know you have a disadvantage.
