Only days after Apple announced the iPhone and iPod touch storage increases, rumors are now circulating that the company is planning an iPhone-centered event on February 26, at which they’ll announce the long-awaited SDK for the iPhone and iPod touch.

Back in October last year, Steve Jobs said he planned to “have an SDK in developers’ hands in February,” so rumors of an Apple event scheduled for late-February are not surprising. In addition to the expected SDK, other rumors this week point to Exchange and Lotus Notes support for the iPhone and new Penryn-based MacBook Pros with multi-touch trackpads.

Furthermore, rumors regarding the 3G iPhone have been fuelled after this week’s news that AT&T is rolling out more 3G coverage in the US, though announcing a new high-speed version of the iPhone so soon after the recent storage upgrade seems rather unlikely. As always, we’ll have to wait and see how this develops.