From Britney Goo -
Beginning this week, AT&T U-Verse customers will have a limit on their Internet usage. However, AT&T is being pretty generous with the amount of broadband each customer can use by giving customers 250 gigabytes per month. Households with DSL will be limited to only 150 gigabytes each month. The change is said to only affect two percent of AT&T U-Verse customers currently who typically exceed the allotted broadband usage. For every additional 50 gigabytes that a customer uses, AT&T will charge him or her ten dollars. Customers can check their broadband usage online, and AT&T will send notifications when a customer is nearing the cap.
Comcast established a broadband usage cap a while back, restricting its customers to 250 gigabytes per month as well. In Asia, Europe, and Canada, it has become very common for Internet providers to limit their customers' usage. Although the concept might seem ridiculous, AT&T said the two percent of customers who use extremely large amounts of broadband take up approximately 20 percent of the network's bandwidth. As a result, other customers suffer the consequences by experiencing a slower Internet connection.
Yet, even though these caps do not seem to have a huge impact on internet users today, it could very well soon affect a wider array of people. With services such as video on-demand becoming more and more popular, it looks like customers will soon be utilizing more and more bandwidth. Does this mean companies like AT&T will be forced to increase their caps? Or will customers simply have to pay more for their broadband and DSL connections? This question can only be answered over time, but Cisco predicts that video will make up more than 91 percent of all internet usage by 2014. For now, internet customers must say farewell to "unlimited" internet access, unless they wish to pay the additional fees.
Source: "AT&T starts capping broadband," CNNMoney