We've narrowed the cause down to a particularly grumpy network device, and given it a small vacation from its duties.
Sorry for the bumpy ride this morning, we really hate it when stuff messes with the LP systems :(
See you on the rift!
We're aware of some problems which are causing players to get stuck in ghost games, and ranked games to not award LP correctly. Right now, our engineers are on the case and looking at possible causes.
We've taken the precaution of disabling ranked until we're confident everything is running smoothly again.