@Riot: Master tier is all well and good but here's what's really needed.
Think of lol's ranked population as a bell curve. Gold+ is the top 20%. Bronze and Silver then should be the "average" tiers, comprising 60% of the population, the bulk of the bell curve.
Below that, introduce "Acolyte" tier. Not wood, not cardboard, or anything stupid and demeaning-this is for the people who want to start to learn the real complexities and intricacies of league's ranked system but are starting from the bottom. Leverage the new match history system to make this tier a place where help is always available and suggestions for improvement are given after each match.
I would suggest an automated post game breakdown for the player, telling them things like
"Your CS is below average on this champion. Try practicing last hitting in a custom game!" Use the system to check the times and locations of deaths and give advice like "a large number of deaths before the 15 minute mark indicate that you should try playing more cautiously in early laning" or "you died frequently near enemy mid turrets-try watching your positioning during sieges" Look at what kind of champions they had trouble with "You were killed by Riven four times. Try building armor early to avoid her all-in."
And then keep a special chat room specifically for players in the acolyte tier to get advice from gold+ players on their climb progress.
Ranked should be a journey, not a frustrating quagmire. Currently bronze players are eternally frustrated by what they feel is an unbearable "Elo hell" and they don't understand what they need to do to improve. Adding a tier built for learning is the first step towards a more healthy environment for low ranked players.