Time Warner Cable's trial of charging people extra for exceeding a set download limit has been a success—they are taking it to four more cities soon, with a new tier that's higher than 40GB.

The key was in metering and charging correctly for overage, apparently, something that trials in Beaumont, Texas helped to iron out. This concept of charging penalties for going over your limit, like your cellphone provider does, works and is probably profitable, moreso than the hard-stop download caps that other providers are enforcing.

The news isn't that TW is looking at 40GB caps, which we knew earlier. The news is that they're going to be looking at potential caps higher than 40GB. In addition, there's a lower-tiered plan for people who want to use less than 5GB a month.

Time Warner's also bringing out usage trackers so people can view their current status, which means there's no surprises when you get billed for 4000GB instead of 40GB. [AP]

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