As you already know, iPhone OS 4 is coming to both the iPhone and iPad later this year. What has been strange about the announcements however, is that the iPad version of the OS is coming months after the iPhone release.
MediaBistro has speculated that the reason for the delay is that Apple is planning a second generation version this fall. Their reasoning is that Apple has announced that all current models of the iPhone (3G+) will receive the 4.0 update in June. The expectation is that Apple will reveal its new iPhone in June. They go on to speculate that the reason for the delay could be technical reasons but they’re not buying it.
In September is when Apple usually drops a new iPod to release just before the advent of the holiday season. MediaBistro is guessing that Apple will drop a 1.5 release of the iPad with some extra features. Perhaps a front-facing camera or mulitasking is in order.
I’m not sure what Apple is going to announce, but this seems a bit far fetched for me. We’ll see in September or June I suppose.