I'm personally waiting to see what the Android 4 / Ice Cream Sandwich / Samsung Nexus Prime will be all about. My Droid X is only 1.5 years old, but I'm pissed at several Motorola-isms and the new phone would let me have a "pure" Android experience. Plus, the rumormill says it will be on Verizon, where I already have a contract. Verizon has, for inscrutable reasons, been offering me new-customer pricing on upgrades to my Droid X, so I might be able to take advantage of that for the upgrade.
I am also waiting for that phone and I'm quite excited about it. I'm also hoping that when I become a Verizon customer I get similar upgrade offers around that timeframe, because that seems to be about the length of time I'm holding onto a phone.
My Nexus One is starting to get pretty flaky, but I do use it like crazy. My wife's 3GS is also starting to act up on her a lot. I wonder if we're going to start seeing more of these phones dying before our contracts are up. We're asking a lot more of these complex smartphones than we ever did of those RAZRs...