I think Pokemon gets better every gen to be honest. 3rd gen was probably the weakest upgrade, but the improvements to the battle system and the moves added make every gen a better experience. I loved 1st Gen, I spent a shitload of time playing R&B in my childhood but they were deeply flawed games with a fucking amazing premise.
So yeah 6th gen is the best because it built on everything before it and made improvements to the formula, X&Y will probably do the same and be the best yet.
