An issue that has been plaguing some owners of MacBook Pro systems is a black-screen bug where systems will suddenly show a black and unresponsive display after performing specific tasks that may be as simple as moving a window, resizing screen elements, or when waking the system from sleep. The problem may show a kernel panic, but generally just displays the black screen and requires users to press the power button to restart the systems.
This issue was first widely noted when OS X 10.7 was released, but it soon became clear that the problem was present (albeit less prevalently) in Snow Leopard and was only exacerbated when people upgraded their systems to Lion. It appears the problem happens regardless of the OS being used, and even happens in Windows running Boot Camp, suggesting the OS and software is not the root of the issue. Regardless, users affected by this problem hoped that the latest OS X 10.7.2 update would address the issue and at least reduce its prevalence if not fix it altogether; however, this was not the case and the problem is persisting for the affected systems.
In response to complaints and the attention that this issue is getting, Apple recently released a knowledgebase article that acknowledges the issue and basically mentions that the Apple engineers are looking into a fix. My suspicions are that this is a hardware-based problem, and as a result I expect that a fix would have to be either in the form of a firmware update, or by Apple offering to service and fix any affected systems. With a firmware update, Apple can tailor how the hardware is used and at least prevent the conditions that lead to the crash, so this is very likely the route the company will take; however, this will depend on what the Apple engineers find.
For now, if you are experiencing this issue, then the most successful workaround found so far is to install the GPU management tool gfxCardStatus and set the system to only run on the integrated graphics processor. Unfortunately this is the slower of the two graphics processors, but will prevent the discrete GPU activation behaviors (either done through GU switching or waking from sleep) that seem to be the root of the problem.
The good news here is that Apple is working on a fix and hopefully will be able to find an easy solution to the problem, but the bad news is that for now there is still no solution, and owners of affected systems will either have to use the workarounds or endure the bug. This bug is nothing short of frustrating for those who are experiencing it, but one mild source of comfort may be that Lion's autosave and resume features do provide a quicker option for restoring your workflow when the problem occurs.