It looks like developers who were interested in making their iPhone apps function in the background are going to have to wait longer than they originally anticipated. Apple has taken the push functionality out of its latest iPhone 2.1 Beta 4 software and it will likely be omitted from the final 2.1 iPhone software. While this key capability was scheduled to be delivered in September, it looks as though Apple will most likely bypass this deadline and wait until version 2.2 of the iPhone is released - probably around Macworld. Apple has recently botched its MobileMe release and is probably more risk averse to releasing what could be buggy software without properly QA testing it first..