When the new league system came out in League of Legends I was winning 25 points with a win and losing 17 with a loss. Get to 100 to become eligible for promotion! It didn't take all that long for me to get promoted a couple of times. I then stopped playing as much (mostly playing a lot of Blood Bowl) and they made some changes to the way league points are calculated. I haven't been able to find any details about how it works, but how it's working for me makes me very sad.
You're not allowed to get demoted below a league type so they've made it so it's hard to get promoted into a new league type. I'm right near the very top of the silver leagues, and when I slowed down I was at about 80 of the 100 needed LP. I've started playing more ranked games again, and the number of points up for grabs seems to have drastically changed. I now seem to win 3 when I win and lose 4 when I lose. I guess this means I don't actually deserve to be up in the gold leagues based on my hidden matchmaker rating?
It's a little frustrating. I'd like to have a chance of getting promoted or demoted, but as it currently stands it looks like I'm pretty much stuck at the top of Silver 1.