Apple stepped up the development of the upcoming OS X 10.7.2 update and released a new beta build of the OS to developers for testing on Sunday. The main focus of the 10.7.2 update is support for Apple's iCloud service, which is Apple's successor to its MobileMe online services and offers a more "Cloud-based" array of options for syncing documents and online purchases as well as managing their use on multiple devices you own.
Until now Apple's iCloud services have been a separate installation for OS X developers and testers, but with this latest update, Apple has included iCloud built into the OS as MobileMe has been in past versions of OS X, and as iCloud is intended to be in its final release.
The OS X 10.7.2 update is anticipated by many Lion users not only because of iCloud, but also in hopes that it will address some outstanding bugs that have cropped up with the initial 10.7.0 release. These include black screens when waking from sleep and when performing some graphics manipulations, shifting application windows and Finder items, touchy HDMI output when using adapters, and even a potential security flaw with handling LDAP-based authentication on enterprise networks.
Apple did issue a quick 10.7.1 update a few weeks ago that included new video drivers to address some graphics problems in Lion, but this small update was released relatively quickly and was likely already in the works before 10.7.0 was released, to address known problems.
In addition to developing iCloud support in OS X, Apple is also working on implementing support for it in various applications, including its iWork and iLife programs. As a result, when OS X 10.7.2 is released, expect there to be numerous updates available for other programs as well. In all, 10.7.2 will be a significant update that is likely due out any day now, so be sure you maintain a full and restorable backup of your system in anticipation of its release.