I've searched around a lot on this topic and I've learned that the Palm Pre Plus Hotspot is free for up to 5GB (Monthly - so I've been told). I've had the Palm Pre Plus for over 2 months now. Last month I went into a verizon store and asked them if the 5GB starts fresh every month and they said yes. I haven't noticed a reset in the amount of GB I've used either month. Should it show 0 GB at the beginning of a new month/cycle? On my data information it says the new cycle started 9/6 but it's still showing the amount of GB I've used since I bought the Palm. Will I have to just keep track myself of how much I'm using a month? Yikes.
What I've noticed is the information available online during the cusp of our billing cycle is really bad, I'd wait another day or two and check. but I've had mine since May and have had no issues with the monthly number being reset and pretty visible (other than those few days!)
hopefully someone will have a better explanation!