Buzz builds for the iPhone 5

A larger screen. Access to speedy new LTE data networks. Built-in mapping software with turn-by-turn directions. High-tech tools to enable your iPhone to work better as a credit card, boarding pass, or retail coupon. A formal launch of Siri, without her beta-test training wheels.

Those are just a few of the new features the buzz machine expects Apple CEO Tim Cook to herald Wednesday morning in San Francisco when he unveils the new iPhone 5 - actually, the sixth in a series that began in 2007, when Apple reinvented the cellphone as a full-fledged touch-screen pocket computer.

And, of course, there may be some well-kept secret or two included in the mix - the kind of gee-whiz innovation that Cook's predecessor, Steve Jobs, liked to announce with his signature understatement, "One more thing. ..."

It's largely a testament to Jobs, who died nearly a year ago, that more than just a small corner of geekdom cares about what Cook will show off when he takes to the stage. Jobs' famed focus on design and detail deserves primary credit for the iPod, the iPhone, and the iPad, the trio of tech tools that in barely a decade drove Apple to the pinnacle of U.S. corporate achievement.

Measured by stock-market valuation, Apple this spring became the nation's largest company ever, worth more than $620 billion to its shareholders. A JPMorgan analyst made news this week projecting that sales of the new iPhone, all by themselves, could add half a percentage point to the nation's closely watched quarterly GDP. In October, when Apple introduced the iPhone 4s, it sold four million in the first three days.

One irony is that the iPhone 5's advances may seem incremental to many of its fairest-weather fans - or worse, may seem to illustrate a contrarian meme that Apple is following, not leading, the market. To wit: Apple may have just won a massive patent-infringement suit against Samsung, but if the iPhone 5 comes with a 4.5-inch screen, well, so does Samsung's popular Galaxy S III.

Apple's aficionados, and even some who count themselves as skeptics, say that would be misreading the significance of the iPhone and other Apple inventions that have transformed the technology market.

Yes, the smartphone business has become an increasingly crowded field, in which other companies periodically leapfrog right over Apple. But if Apple stays true to form, it will leapfrog right back with the iPhone 5 and the companion iOS 6 operating system, which Apple previewed in June for developers.

Even without Jobs' sly "one more thing"s - or his black turtlenecks and dramatic flair - Apple maintains a large capacity to surprise, said Tim Bajarin, president of California's Creative Strategies Inc., who has been keeping tabs on Apple for more than 30 years.

"It would be surprising if Apple didn't have other surprises that never got out in the rumor mill," Bajarin said this week. "Ultimately, it's hard to speculate."

Still, iPhone 5 speculation has become an almost full-time pursuit in tech world. Here are some of the features Bajarin and others say Apple is likely to offer in the new smartphone:

A bigger screen. Unless Apple shocks everyone by offering it in two sizes, the buzz seems to have settled on this much: The iPhone 5 will offer substantially more screen real estate than its 3.5-inch predecessors, a move Bajarin attributes simply to "keeping up with consumer demand."

The key challenge is how to do so without creating a phone considered too large, too heavy, or too fragile. One easy prediction is that iPhone 5 will devote a larger fraction of its face to the screen. Many consider a slimmer iPhone likely, too.

Hardware upgrades. These are always a given. Expect longer battery life, a fancier camera, and faster electronics, along with the capacity to use them, finally, on the carriers' fourth-generation LTE data networks.

Near-field communications. The jargon may not mean much to you, but Apple is plainly hoping you'll appreciate what this technological advance will do - especially when teamed with Passbook, a feature Apple is expected to include in iOS 6.

Forrester Research's Charles Golvin describes Passbook as a "repository for digital assets" - items like movie tickets, airline boarding passes, and Starbucks coupons that you may already be keeping on your smartphone but that will now have a single vault.

With Passbook and near-field communications, the phone could also become a full-fledged payment device, perhaps even allowing users to make purchases through their iTunes accounts, Golvin said.

FaceTime via cellular. Skype has made video-calling almost commonplace, but Apple's version is more refined than most. Until now, it has been available only when connected to WiFi. Expect the cellular version on the iPhone 5 - and if you get hooked, a step up in your data consumption.

So is everybody waiting for Wednesday's unveiling with bated breath? Hardly - not even among the technologically sophisticated.

Harold Hambrose, CEO of the Philadelphia design-consulting firm Electronic Ink, says he won't be rushing to replace his iPhone 4s. Although he credits Apple as "a catalyst for other people to become innovative," he says it has been overtaken on some features, such as typography, by competitors such as Microsoft.

"The fan club will be excited" by the iPhone 5, Hambrose said. "Typically at this point, the innovations will be missed on most of us, because we're not all that fascinated by the subtleties. But for the geeks out there, it'll be night and day."