Sarah and I bought each other smartphones for our birthdays. They aren't any of the big so-called feature phones like the Droid X or iPhone 4. Rather, we got Samsung Intercepts for Virgin Mobile. I won't go into all the reasons that we went the low-end route but you can shorthand many of them with one word, "money".
In the past, when I saw people with their heads buried in smartphones I always looked down on them for what seemed like their complete obsession with a cell phone. Now that I have one of my own, I totally get it.
The phone is great for letting me check my e-mail pretty much anywhere I want. It has a slide-out keyboard which means that I can relatively rapidly type e-mails and text messages. The screen is bright and the camera isn't awful. And all of that is nice, but what really makes it a great device to own is that fact that it's basically a general purpose computing device that you can carry around with you and that extends the Internet to places far from a telephone line, Ethernet jack, or wi-fi network. I've used the phone to stream Internet radio stations in the car. I've checked Internet prices on products while in the store. I can update my online notebook full of books to read and ideas to ponder from just about anywhere. We've used it to pull up Google Maps in the car when we got turned around in a part of town we rarely visit. I can catch-up on all the latest baseball and hockey news from just about anywhere. Want to know what the weather forecast is? I can pull that up easily too. Forget something to read during a bus ride? No problem. Pull up the New York Times or the USA Today.
In short, having a smartphone is a little like carrying around an always-on, usually-connected laptop that also happens to fit in your pocket.