They are being designed to have touch screens, send messages, even surf the Web. What's happening to phones is similar to what happened to typewriters and word processors 15 years ago. Back then, we used one device to create most documents - and that's all it did. Word processing was more than a feature, it was an end in itself. Today, computers handle most word processing, along with a slew of other functions.
Typewriters still exist, but they're less important.
Now the same thing appears to be happening with voice. Today, we use phones for voice communication, and with just a few exceptions, that's all we use them for. In the next few years though, some people think smartphones and similar devices will turn voice into just another feature. Some primitive smartphones are already beginning to arrive on store shelves, though the market won't really heat up for another year or two. Perhaps the best-known example on the market now is the Kyocera pdQ, a bulky phone that doubles as a Palm handheld.