I installed this yesterday and only had 23 sms over my plan. By this afternoon I had 113 over my plan. I noticed it updates around 10pm everyday but it appears the google voice sms is charging when it was suppose to not do that. I checked my settings and it is not set to forward to my phone and when the texts came through they all said google voice and was not in my iphone message app.
*******Well come to find out that there is a delay in usage detail so it is working after all so this is wonderful news!!!!!!!
The last sms charge was around 1:43am 12/13 and I installed google voice at 9:43 am 12/13 according to apple. So Verizon customers this is great news***** The only downfall right now is it does not work for mms so hopefully google will add this feature soon.