I find most of the bloggers and posters don't know what they are talking about. Fact is the wm6.1 can do USB tethering and some phones like my htc TP2 do it via BT and wifi routing too.
What most are confused with is the fact that Verison ALSO offers their software for a monthly charge. That does not mean they won't let you use your software but are quick to warn you that you cannot expect Verizon to give you free tech support on it. You need to deal with the 3rd party software maker for support.
The real problem is that not all 3rd party software works flawlessly and some cause problems in your phone that could violate a warranty.
For my phone- I have found PDANET works great with no issues. It is a USB cable only connection. It also allows the phone to charge through the USB cable which is great for long term usage.
There is a bare minimum 3rd party free software that is called "Mobile wifi router" but it has trouble maintaining connection, and greatly overheats the phone during use. I would not recommend this.
What I use is a $$ package that has three forms of connection and allows for wifi routing up to 5 connections at once. It works great but is $25 as I recall. The battery does not overheat but using it shortens the life so you need to have the phone plugged to a charger in if you are going to have it connected for hours at a time. If a call comes in you lose wifi router.
I have both PDANet and WMWIFI Router installed with full knowledge of Verizon. They don't care and told me so. This is Verizon NOT AT&T. It's not about laws. It's about company policy.