In May of last year Comcast announced they would be experimenting with metered billing in several trial markets. Users in those markets suddenly found themselves facing a usage cap of 300 GB a month. Users who consumed more than the allotted bandwidth would then be charged $10 for each additional 50 GB over the cap they traveled.

The 300 GB has been in trials in Nashville for some time, but back in August Comcast expanded these trials into the Central Kentucky, Savannah, Georgia and Jackson, Mississippi markets.

Now, DSLReports user Shinrin directs our attention to new information on Comcast's usage cap website that indicates the cap trials have expanded into Huntsville and Mobile, Alabama, as well as Charleston, South Carolina.

The expansion comes on the heels of news that Comcast is also copying Time Warner Cable and testing another metered plan they're calling the "Flexible Data Option." That plan offers users a $5 discount off their bill if they're willing to agree to a 5 GB monthly cap. That $5 discount evaporates immediately should you choose to seriously use the tier, with users charged $1 for each additional gigabyte consumed.

According to the Comcast website, Economy Plus users in the trial markets who don't volunteer for the 5GB plan automatically face the 300 GB cap. Unlike other capping efforts where carriers claim charging you more "improves the consumer experience," the Comcast FAQ doesn't even bother to even justify why they're imposing these limits. The e-mail sent to users however insists that having their previously unlimited connections capped creates "more choice and flexibility."

The cable industry used to claim that such caps and overages were necessary due to network congestion, but after years of such claims the industry in January admitted the congestion justification was false. Such usage caps are simply a way to protect TV revenues from Internet video while raising rates on already expensive broadband in uncompetitive markets.

Comcast has had the technology in place for years to implement metered billing; what they're conducting now are effectively marketing and psychology experiments to identify the best way to get consumers to sign off on the idea. US consumers have generally been smart enough to know a rate hike when they see one, and their response to having metered billing foisted upon them has traditionally not been positive.

However, when users have no other broadband options available to them (or all of their options also implement metered billing), voting with your wallet becomes impossible. Granted if you ask Comcast, there is no competition problem, and certainly no competition problems specifically in the markets they're targeting with these trials.