On last week’s Windows Weekly, Brandon Watson mentioned that tethering support in Windows Phone would be dependent on the wireless carriers. This is, unfortunately, incorrect. but since he wrote it then it has been picked up by many blogs and false information is flying around the web like wildfire.
To be clear: Windows Phone 7 does not support tethering at all.
The intention is to add this capability over time, of course. But it’s not there for v1. Which is unfortunate because this is something I really need to have in a phone and hope it’s in v1.1