Bad. It's a lot of stuff and if you're interested in reading up on it all, this is a good place to start.

If you want a TL;DR on what this can mean for you. So you know how on TV, cable companies can charge you extra for 'packages' for access to specific channels? They can do that for websites now. They can also throttle/slow or outright block your connection to sites or apps they simply don't want you to see (competitors and such). Basically allowing corporations to take control of what was a free internet. Everything has the potential to be locked behind some sort of paywall.