There is reason to believe that Apple will release its next major software update to iPhone owners worldwide at its upcoming event in San Francisco. Beta builds of the iPhone software 2.1 are said to have been intentionally stripped down by Apple, in order to keep its contents under wraps.

“Let's Rock,” Apple's upcoming event taking place at Yerba Buena Center for the Arts (located in San Francisco) at 10:00 am (Pacific) tomorrow, is said to be the host of many surprises, including a new version of the iTunes media player, revamped iPod nanos and iPod touch, and... yes, iPhone 2.1, let's not forget that. While most rumors are consistent with the facts, iPhone 2.1 doesn't really seem to fit in anywhere. However, given its “must-have” nature, should it be able to fix some of those nasty 3G connectivity issues, and other reported bugs, the event would indeed be the right place for an official unveiling.

As such, ars technica claims a little birdie told it iPhone 2.1 is to be released on September 9th, packing additional parts, not revealed by beta testers. This is because, these parts “were specifically removed from developer seeds in order to keep them secret from the world,” the site notes. Features not tested outside of Apple's own labs are reason enough to both get excited and be worried, the site adds. Nevertheless, an update is always welcome, especially when it promises long-awaited fixes.

Also “confirmed” for the event, the tech-based site says, is iTunes 8.0. The topic has been a hot one since digg's founder, Kevin Rose, dished out the first details regarding its new functionality. The tipster even stated that “much of what Rose claims is in iTunes 8 is correct as well.”

Back to iPhone 2.1, we know that Apple has slapped it with a new background push notification feature for third-party apps, as well as directional GPS. Also known as a fact is that Apple, for one reason or another, decided to remove the push notification feature from one of pre-release builds of iPhone 2.1. Here's to hoping that tomorrow sheds more light on all these exciting allegations.