So after seeing the US tier lists, the ones here posted that are kinda fail and that osaft dont post anymore tier lists, I thought lets do a good tier list.
Is not my intention do a tier list for myself, instead I encourage experienced players to post their opinions and suggestions to then change champion positions, I dont know all the champions, so to start I do a provisional list for what I see in most games that I hope it wil be changed after people post their suggestions.
Tier 1 (they will help a lot to win the game): Ezrael, Heimerdinger, Kayle, Shaco, Xin Zaho, Soraka, Taric, Amumu.
Tier 2 (they will help to win the game): Ashe, Annie, Gragas, Kassadin, Katarina, Shen, Sion, Garen, Morgana, Tristana, Udyr, Vladimir.
Tier 3 (what it should be balanced chars): Anivia, Janna, Karthus, Nidalee, Poppy, Singed, Zilean, Fiddlesticks, Warwick, Rammus, Alsitar, Pantheon, Twitch, Sivir, Akali, Gankplank, Master Yi, Nasus, Veigar.
Tier 4 (they will shine if your team if doing good, but prolly fail if not): Corki, Cho,gath, Dr. Mundo, Malphite, Olaf, Tryndamere, Twisted Fate, Nunu, Blitzcrank, Jax.
Tier 5 (hard to place them in teams, they need specific and coordinated teams): Evelyn, Kennen, Malzahar, Mordekaiser, Ryze, Kog'Maw, Teemo.
Note 1: I think LoL is finding some kind of balance, that means with the excpetion of tier 1, the other tiers I dont find really an awesome difference between tier to tier, just small differences that makes them a bit better.
Note 2: Some chars can fail in most teams, but they can became really good with the right setup, for example, TF can be bad in lot of team setups but can be great in a team teleport setup like shen+pantheon, or kennen can be good in an AoE team.
Note 3: Waiting your suggestions to change the list.
Updated with the new ranked mode.