Apple has quietly begun development of Mac OS X 10.7, the next iteration of its OS and an as-yet completely unknown animal, MacRumors informs.That Apple’s engineers are already hard at work figuring out what to do next with the lean, Intel-only software at the heart of the current Mac OS X ‘Snow Leopard’ OS is no great surprise. Work has to begin sometime, and Apple is a company known for a five or ten-year planning cycle.Prize for first glimpse at what’s to come goes to MacRumors, which reports a post in a database of changes to the open source “launchd” framework, which apparently, “oversees booting of Mac OS X