I have resisted signing up for tethering with AT&T because I would have to go from my current 5 GB to 2 GB of data, and then pay $20 for no extra data. Now you at least get extra data.
I am unsure of how this new plan works exactly though. If the increased cap is only for tethering, how will overages for your normal data work? I assume that if you use more than 2 GB without tethering you will be charged overages and that there is some way for them to know what data is used for tethering and what isn’t.
This is already proof that the competition from Verizon is making a difference.