As I walked the floor the last couple of hours of CTIA Wireless 2007, watching booths close and folks scurry around to finish up and make their flights back home, it became obvious to me that not one device stood out as the breakthrough product for 2007. And, while ever-more-sophisticated smartphones and other advanced data-centric handsets were everywhere you looked, it was a bit of a surprise to see the strong persistence of voice-oriented feature phones.

As was the case at the Consumer Electronics Show (CES) in January, 3GSM in February, and CeBIT early in March, the specter of Apple's iPhone appeared to take the wind out of a lot of sails at CTIA. And the iPod/phone/Internet device wasn't even on the show floor; its only (and brief) appearance occurred when AT&T Chief Operating Officer Randall Stephenson took out an apparently working iPhone during his keynote on the first day of the show.

It was the first time the iPhone appeared in public since Steve Jobs unveiled the highly-anticipated gadget during Macworld during CES a couple of months ago.

Stephenson said over a million people have already asked to be notified when the iPhone ships. It'll be available from AT&T (formerly Cingular) and Apple directly sometime in June.

Before you knew it the iPhone was gone, hustled out of the conference center by Apple, no doubt to help maintain the mystery surrounding the device, which only an elite few have actually held in their hands.

While a lot of vendors have been quick to point out that everything the iPhone offers is available in many of today's cell phones and smartphones, they seem resigned to the fact that nothing they've come up with recently has generated as much excitement and publicity.

However, most platform and device manufacturers we've spoken to, whatever they think about the device itself, have come to embrace the iPhone as something that can only lift up and draw positive attention to the cellular-wireless industry as a whole.

And while no device or service matched the impact of the yet-to-be released iPhone, the overarching theme of the show is noteworthy because it matches what Apple is attempting to achieve with the iPhone.

You can sum this theme up with one word: Simplify.

Be it platform, device, application vendor or carrier—the word on the floor and in one-on-one meetings with wireless companies of all stripes was trending towards making the whole mobile experience better for end-users by offering products and services that are easier to use.

It appears the wireless industry has taken the lessons learned from Web 2.0 and brought them to the mobile handset.

For example, while SMS messaging is huge, with tens (if not hundreds) of billions of messages exchanged last year, far fewer folks took advantage of that service's multimedia cousin (MMS) - thus far a disappointment to carriers - because it is still too complicated to use for many folks. That is if they even know the feature is there.

Either way, if more people MMS messaged each other they'd certainly feel like they're getting more out of the pictures that are stuck on their camera phone, and the vendors supplying these services would get more for their investment.

On the smartphone front, Nokia provides a neat little free application and service called Lifeblog, which makes collecting, storing and sharing multimedia content relatively easy. Content shared from a phone is viewable on a phone or PC, and it can include photos, video clips, messages, as well as text and audio notes. Users can supply contextual information, such as calendar entries and location data, with their diary as well.

While the end-user gains a better and simplified way to share all sorts of mobile content with others, the industry as a whole gains by getting people to actually use their phone for more than voice calls and SMS.

This is the aim of carriers and others in the industry—to find ways to target people with content services to raise Average Revenue Per User (ARPU) as voice revenues decline. This also includes, somewhat inevitably, better ways to market to and advertise to consumers on their cell phones and smartphones.

Of course, with mobile advertising, the last thing any of these players want to do is become so intrusive that it turns people off, a real danger for something as personal as a cell phone or smartphone.

Many of the companies we spoke to at the show emphasized their awareness of this last point.