Well of course these are opinions. That's why I usually don't let reviews impact my purchasing decisions. But there aren't many people that would argue that Infamous 2 isn't as good as Second Son. Not sure if you've actually played the games, but I played all 3, and Second Son is CLEARLY the best. And it got a lower score from IGN than its predecesor.

My opinion is, games are getting lower scores because the game doesn't contain things people may have hoped for, instead of reviewing it for what it is. For instance, you read alot of comments now saying they didn't do anything new. Well, if they have a winning formula, why reinvent the game just because we have new consoles? Many would look at the Infamous 2 score and think it's a better game. Although it's a great game, it's clearly not better.