Of course, some people believe that instead of an iPhone, Jobs could announce the iTV, which would establish a link between the computer and television.
No matter what the specifics, many people are wondering what all the hype is about.
If announced, it would just be a phone that plays music files -- a technology that's already available from most of the major mobile phone manufacturers. But some think Apple could do for cell phone design what the company did for mp3 players with the iPod.
"Apple has evolved in the last two years, I think, from a technology company to a consumer experience company," Yigit said. "So that's why there's interest from the consumer perspective."
Yigit said that current phones had clunky, inconsistent menus and functions that kept most users from actually trying advanced features.
Apple's renowned design prowess could change all that, making cell phones easier to use while opening up new features to users who might be intimidated by the buttons and menus that plague the current generation of mobile handsets.
"The reason why Apple can create so much buzz and excitement is that their consumers love their products, and they create great products," said Gene Munster, an analyst at Piper Jaffray. "If Apple couldn't create the quality of products they do they wouldn't have this buzz."
That might explain why a Solutions Research Group survey found that 16 percent of Americans older than 12 said that an iPod phone was a great idea for them personally.
The positive consumer results from Yigit's survey indicate an Apple phone could grab between 6 percent to 8 percent of the U.S. handset market in the first year after its launch. That's between 10 million to 15 million units in its first 12 months and would make the iPhone more common than RIM's popular BlackBerry smart phones.
That's a vote of confidence that is not just based on blog buzz, but the company's track record of making things that people want to buy. The iPod -- introduced to the world just five years ago -- has been sold more than 67 million times and is helping bolster sales of other Apple products.
"If they ever did announce an iPhone, if Apple puts their industrial design magic behind it, he could end up with another top seller," Bajarin said. "While we have no idea what he's going to say on Tuesday, those of us who follow him are going to be watching quite closely because we know what he says can be game changers for the industry and cause significant pain to competitors."
Neal Karlinsky also contributed to this report.