Isn't the $10 a month extra lines only available on certain plans? Right now I have the cheapest 450 minute plan plus texting and internet. If I would have to upgrade to a bigger plan, then no way is it worth it. If I could keep the same plan, adding $10 a month to a bill to get a new phone every year is so wroth it!
Recently I bought the droid razr because my wifes line was eligable, from a third party website at a deep discount. Then verizon had the bogo offer, so got a razr maxx for myself and my wife.
What is funny is about a year or so ago I got a verizon galaxy tab. And that line was eligable for upgrade so I used that upgrade and a basic phone line we have to take advantage of the bogo offer. All in all I made money on the deal.