Ok, I realize that with 2.2 you will be redirected when tethering with the native option. The weird thing is I have been using the native option on Lithium Mod and Bugless Beast.....until today. While tethering, the Droid suddenly rebooted and I can no longer tether without being redirected. I use a 3rd party app and have no issues, so its fine.
Still, I just wanted to mention it as I thought it was kind of weird. I didn't even know about the Mobile Broadband plans until this happened.