If the company follows past practice, it will offer developers a preliminary version of iOS 5 at WWDC, along with an SDK, or software developers kit, giving them several months to work on new apps or update existing ones with features specific to the upgrade.
Gottheil, for one, is uncertain what Apple will add to iOS 5, or bring to the table in the next iPhone.
"It's getting harder and harder to figure out what to add to the iPhone to make it better," he said, echoing other experts who have already labeled the next iPhone as possibly a less-compelling purchase than earlier refreshes of the line.
Apple will also reveal in more detail Mac OS X 10.7, aka Lion, which was first announced in October 2010. At the time, Apple said Lion would ship sometime this summer.
Recent revelations from developers, however, indicate that the next update to Snow Leopard -- Mac OS X 10.6.8 -- will include a Mac App Store update that allows customers to upgrade to Lion without physical media. That has spurred talk that Lion's release is imminent.
It's probable that Apple will use WWDC not only to tout Lion, but also to announce its price. Two years ago, Apple used the WWDC platform to narrow the launch date of Snow Leopard, Lion's predecessor, and spell out the upgrade's $29 price.
Prior to that, Apple had priced its operating system upgrades at $129.
"Reducing the price [of Snow Leopard] did not negatively affect revenue," said Gottheil. "I expect them to offer a low-priced upgrade to Lion as well."
Doing so will let Apple again contrast its upgrade pricing with Microsoft's, as it did in 2009 prior to the debut of Windows 7, Gottheil added.
The WWDC keynote will be Jobs' second public appearance since he stepped away from Apple last January. His only other time in the limelight was in early March, when he took the stage to introduce the iPad 2.
"Certainly, he's well enough to go out in public," said Gottheil of Jobs' plans to participate in the keynote. "If nothing else, he wants to demonstrate his ongoing relationship with the company."
Jobs' time on stage would be the perfect opportunity to announce his return to work at Apple, or to set a timetable for that, said Gottheil.
The WWDC keynote is scheduled to start a 10:00 a.m. PT on Monday, June 6, the opening day of the conference, which runs through June 10. Apple sold out WWDC in under 12 hours, a record, when it put the $1,599 tickets on sale March 28.
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