Droid w/ Verizon here... I use anywhere between 500MB on a low month to 1.1GB on a high month and average somewhere in the middle most months.
I sure hope Verizon doesn't follow AT&T's modifications. I think it's stupid for AT&T to make their customers pay $15 for only 200MB and $25 for 2GB. It's just not the right configuration to go from $30 for 5GB of data. A better price plan would be $15 for 500MB, $20 for 750MB, and $25 for 3GB. That sounds more reasonable and caters to several tiers of data users. Low, Medium, and High.
Whatever Verizon does, I'll be grandfathered in. Not that I use the 5GB, I just think it's the right price/GB combination.