Soon after Apple's developers got new builds of Mac OS X 10.6 Snow Leopard to play with, other, less select testers received pre-release versions of Mac OS X 10.5.6, as well as a new beta build of the iPhone SDK.

MacRumors is reporting that Mac OS X 10.5.6 Build 9G21 was seeded to developers packing “the usual laundry list of bug fixes and improvements across a variety of services.” Seemingly, the update moves the notebook trackpad preferences into its own preference pane in the control panel, “just like on new laptops,” according to the same source. Some may recall that one of the features emphasized by Steve Jobs at Apple's recent notebook event was four-finger multi-touch gestures. Well, according to the release notes for Mac OS X 10.5.6 build 9G21, the update doesn't bring said gestures to Apple's older laptops that support multi-touch gestures.

There's more! Allegedly, there is also indication of Blu-ray support in the pre-release version of OS X 10.5.6. Following the release of Apple's latest maintenance and security update for Leopard (10.5.5), many suggested that the company's next focus should be adding Blu-ray support in its next update to Mac OS X Leopard.

Kevin Rose, who has been the source of several Apple-related rumors for quite a while, posted a blog entry, as well as a YouTube video, ahead of Apple's music-related event in San Francisco, “Let's Rock,” hinting at Apple's plans with the iPod line and the iTunes media player. Rose added that an upcoming version of Leopard, Mac OS X 10.5.6, should include Blu-ray support and, while pretty much every prediction Rose had to share turned out to be true (the new iPod line, iTunes 8.0 and iPhone OS 2.1), Apple was yet to confirm the burning Blu-ray rumor.

However, statements coming from Apple's executives at the Town Hall notebook event this month indicate that Blu-ray is still a no-no. "Blu-ray is just a bag of hurt,” said Apple CEO Steve Jobs, when pressed about Blu-ray support in Macs. “It's great to watch the movies, but the licensing of the tech is so complex, we're waiting till things settle down and Blu-ray takes off in the marketplace," Jobs added.

There is also no indication as to when Mac OS X 10.5.6 will be released.