Part of the shock the OP had is their suprise at 2.1GB putting them in the top 5%. That seems believable to me. I worked in a residential ISP and once ran the numbers on about how much data people use. Something like 90% of people didn't go above 5GB or so. And this was on residential DSL, not on mobile internet.
Of course in theory this is going to reduce the average usage of AT&T users, since someone is always on the top 5% (by definition 1 in 20 customers will be affected). It also seems a little unfair to have a rule that you can't know in advance.
5 GB makes the 250 GB Comcast cap look overly generous, when I can tell you from experience that 250 GB with two people using the Internet on a daily basis is too little.
New games come in at 10 GB or more when you are downloading them from places like Steam, add in two people downloading new games and you can easily see 100's of GB's going to just gaming. If I rebuild my Windows desktop and have Steam re-download all of the games I tend to keep locally I myself use about 150 GB of transfer. On top of that comes watching TV Shows (on Hulu/NetFlix) and movies (iTunes/NetFlix/Hulu) and various other downloads. The latest Mac OS X update weighed in at a hefty 1.38 GB, split across 4 devices.
Granted, I am a technology person, I am a programmer, I spend more time behind a computer than doing almost anything else (including sleep). My usage pattern is going to be vastly different compared to grandma and grandpa that check their email. The thing is though that I want higher quality content delivered to me instantly, Hulu's 480 is nice and all, but I would love to have it in 720p or 1080p for my large TV. All of this uses up bandwidth/transfer.
As for mobile data, I don't tend to do a lot of streaming of music and the like, so far I haven't had any issues with going over the allotted 2 GB from AT&T, that and when I do want to stream I am near Wifi.
Yet as another anecdote, even when watching Netflix streaming basically every night, and downloading the occasional Steam game, I have never once passed my 250 GB Comcast limit. Much as I dislike these kind of caps, it is pretty damn hard to go over 250 GB. That's, what, 200 hours of reasonably high-quality streaming video? 300+ Linux ISOs (the only reason you run bittorrent, right?)?
Sadly, I don't think "unlimited" internet is a sustainable model, because generally speaking every bit you send costs the provider money, and the rise of things like Youtube mean that people actually use more bandwidth. However, 250 GB plus a reasonable per-GB charge after that should be reasonable for a very larger percentage of users.
I don't run bittorrent at all (nobody on the home network does), mainly has to do with my current employment. Between my room mate and I we do 200 GB on average, we've had one warning sent out for getting to 245 GB.
Here is our yearly usage chart: http://i.imgur.com/wZbU1.jpg (since the router/gateway was last rebooted). Do note that there is NO illegal downloading at all. NetFlix, Hulu, Pandora, Spotify, Steam, Dropbox, WoW and many others.
I see no problem with having the monthly plan include 250GB of data. Where it gets stupid is what happens when you go over. Rather than charge you extra, they give you a warning and then cut off your service entirely.
This completely baffles me. Why pass on the opportunity to collect more cash?
>Something like 90% of people didn't go above 5GB or so. And this was on residential DSL, not on mobile internet.
That's skewed to people who don't value a fast internet connection. Those that do have moved on from vanilla DSL to DOCSIS based cable, FIOS, U-verse, and other technologies. I'm not surprised that plain jane DSL is the home of retirees and people whose needs rarely go beyond a facebook/web machine.
Funny thing is that I'm with two providers the conventional "wisdom" here and at others sites like reddit consider to be garbage: comcast and tmobile. Comcast is honest with me and publishes its 250gb cap. I get 13/3mbps for that 250gb. Tmobile gives a 5gb cap on my S2 before throttling, thats 5gb on a fast HSPA+ connection. No games, no BS(well by corporate standards), and I can check my usage easily. I can't imagine having to deal with AT&T. Didn't they just unilateraly make everyone pay extra for text messages a couple months ago? Its horror stories all the way down. Meanwhile, I'm going pretty good with my supposedly "bad" providers reddit and consumerist likes to rant about.
Of course in theory this is going to reduce the average usage of AT&T users, since someone is always on the top 5% (by definition 1 in 20 customers will be affected). It also seems a little unfair to have a rule that you can't know in advance.