If you're a current or prospective T-Mobile customer and you're partial to using that data connection for more than one device at a time, there's good news. The gents at TmoNews got their hands on an internal memo that outlines bumps in T-Mobile's tethering policies that went into effect yesterday. Before yesterday, the $70 unlimited data plan included 500MB of of Smart Phone Mobile Hotspot (tethered data) and an option for a $30 2.5GB add-on. Now you can get 2.5GB for $20 extra, saving $10 a month.
But wait, there's more! The $30 add-on has been bumped from 2.5GB to 4.5 GB, and the $40 add-on now gets 6.5GB of sweet, sweet USB or Wi-Fi tethering action. Existing customers will be migrated to the higher tiers for the same price - you'll have to manually set a lower tethering tier if you want to save a bit of money. That's combined with the 500MB of tethered data that's included on T-Mobile plans by default. If you approach your tethering limit, T-Mobile will call you with an upsell to the next-highest tier.
Even T-Mobile seems a little confused as to when and how the bumped tethering options will go into effect. According to a T-Mobile representative I spoke with, the plans are not actually available yet. An Android Police writer who uses T-Mobile saw no options at all for tethering on his $70 unlimited plan. (Perhaps the carrier is actively upgrading its site.) Throw in the general uncertainty of T-Mobile's data tethering tracking vis-à-vis user agents, and it's more than a little confusing. Give customer service a call if you're having trouble trying to figure out your options, but realize that they may not be able to talk about these new options yet.