Comcast cable bandwidth distribution in neighborhood nodes has usage checked automatically by node. If the set of users on your node is not using much bandwidth, then you can download a lot every day and not attract the attention of Comcast (at least in my area so far). Your speeds of download can be very large too. At least this was how it was explained to one of my friends who for some strange reason chose to live in a quiet apartment complex full of "old" people. The old fogies don't really use up the bandwidth, so my friend gets to download well over the limit each month and at high speed. So far, comcast has not contacted him.
I am not sure what area you live it but that is not how it works where I work. ( I am a tech for Comcast.) The only time Comcast will care about your download is if you go over your 250 gig limit per month, otherwise they don't care. As for internet slowing or getting faster because of how many people are on it, it is not like DSL, the amount of frequency's we have is more then enough to support any number of customers on a node. (could be between 50-500 on a node). Therefore even if everyone is on at once it will not slow down. It does not get faster or slower based off of how many people are using it, it is all controlled by a program file that is stored in your modem. This file controls all of your internet speed. Your friend has not been contacted because there are people using a lot more bandwidth per month then him so they go after them first. They will eventually get around to him and give him a warning, if he goes over his 250 gigs again they will cut off his service for 6 months.
As for them monitoring they chose people with very high bandwidth usage and even then most of the time they need a court order. Think about it if we where really watching everything, one I would be fired for using this site, two child pornography sites would not exist. The biggest one that Comcast would care about is Universal since we now own them. What it really comes down to is that even with the new laws they cannot look at what you are doing on your internet unless they have a valid reason. Even then there are still hoops that need to be jumped through. Its not as easy as lets see what little Johny is looking up today.
Finally, that law is defiantly more targeted towards movies put out by huge company's, aka universal, Fox, Disney etc. Anime sites like this is low priority.
Edit: And as for the main topic of this thread Comcast has had its internet usage limited to 250 gigs for a couple years now, it is not a new policy from the article mentioned here, nor will they be decreasing it from that amount. This is because of a law put into effect by the FCC when we bought Universal to prevent us from having to much "power". We most keep our limit where it is, and we have to provide "affordable" internet to everyone, we are not allowed to throttle our internet in any way. This is to prevent us from effecting services like Netflix in an attempt to make people use our video service vs. one that streams online.
