The problem with reviews is that the underlying measure is only implicit. There is no real way to make a really objective review because people have different expectations and different playstyles... So even if a game has a good or bad review... the real question is if that review is actually reflecting my own preferences.
I bought the "game of the year" editions of oblivion and borderlands because they had stellar reviews... but they were simply awful in my opinion because they had a real bad main story and were full of uninteresting side quests with no real meaning to the overall story. Some people like the "freedom" and "feeling of exploration", but it just felt like wasting my precious time with a game without clear focus and without something to tell/express.
Final Fantasy XIII was the best game of this generation for me. The characters were portrayed with all their strenghts and weaknesses, doubts and fears... The story wanted to make you think about the holocaust and the effects of propaganda. FF XIII was the one game, that did not felt like a movie... it felt more like a theatre play, that doesn't only want to entertain you but wants to make to actually think about some moral dilemmas. If you review it with a focus on the story, it was something groundbreaking....
If you seek "exploration" in FF 13 you may be disappointed, because that was never the main focus of FF. So what do the mixed reviews in the US/UK really mean. Is it a bad RPG, a bad JRPG, or just a bad game for most US/UK Gamers who really expect something like Bioware or Bethesda would do... or simply that the reviewer doesn't like this particular game.
I for myself found that sticking with the same developer teams is a good way. If you appreciate the philosophy of the team you will most likely have fun with other games of the same team. I have sticked to SquareEnix, Capcom, Konami, Level5, Naughty Dog and Insomniac and selected games from Namco/Bandai and Tecmo/Koei for years and have learnt to stay away from Activision, EA, Bioware and Bethesda, THQ and Rockstar except for selected games. That kept me safe from major disappointments except Dragon Age, Oblivion, Borderlands, Sacred 2 and Mass Effect 2, where I was "blinded" by reviews. That doesn't mean these were bad games, they just were far from what I personally expect from gaming.