Story updated with additional details from the iPhone event.
Less than a week after the Easter weekend debut of the much-hyped iPad, the media spotlight is again shining brightly on Apple.
Journalists have converged on the tech giant's Silicon Valley headquarters for a sneak peek of the new iPhone operating system, which is expected to power the iconic smartphone, the iPod Touch and the new iPad.Apple CEO Steve Jobs has kicked off the event with an update of the company's iPad and iPhone sales, according to a liveblog from the Gizmodo Web site. Some 450,000 iPads have been sold through today, he explained, adding that Apple has also sold a massive 50 million iPhones since the smartphone was launched in 2007. As with all things related to Apple, there has been plenty of speculation about Apple's plans for version 4 of the iPhone OS. While fans are expecting multitasking of third-party apps, there has also been talk of GPS navigation and even a major mobile advertising push that could encroach on Google's (GOOG) turf. During the launch event, Jobs duly confirmed that iPhone 4.0 will offer multitasking of third-party applications, and promised that this can be achieved without draining the smartphone's battery. Apple also discussed new "background location" features for navigation, as well as enhanced data protection, which is clearly aimed at enterprises. Rumors of a major Apple push into mobile advertising were also confirmed at the launch event as Jobs unveiled iAd, which lets developers embed ads within applications. iPhone 4.0 will be available in the summer, according to Gizmodo's liveblog, although a preview version of the OS was unveiled today. The new operating system will be reportedly make it to the iPad during the fall.