Another route... In the likely event that Verizon doesn't do discounted pricing for non-contract accounts, you could get the best possible phone available every 20 months with a 2 year contract and sell it sealed in the box to fund your unsubsidized upgrade path. Yeah, it locks you up with the carrier, but if you don't care about that, you might as well get what's coming to you free than pay the same thing month-to-month, getting nothing. Definitely want to hit the 3rd party retailer channels to get better pricing.
That's what I may do. Smartphones are quickly approaching overkill as far as hardware, with quadcores just around the corner. Just like PC's, a couple year old model really won't impact you and will do everything you need. These phones are about there right now, but will need more processing power and ram to become laptop replacements.
But figure buy retail, sell in 10 months and get another, then another 10 months hit your 2-yr program discount...
new 2-yr contract for $250
sell in 10 months for $250, net $400 for a new phone
sell in 10 months for $250, net new phone with subsidy = $0.
That works out to about the same on average as phones on the 1-yr plan, you're out a bit more between upgrades but get an extra $70 or so with the 2-yr discount vs. 1-yr. So you have to hassle with EBAY, but unless you are between contracts (like myself and others), it's not a big deal. I'm going tobeeating $600 retail in here somewhere unless I can hold out 6 more months (unlikely).