That official PlayStation blog is turning out to be a great source for up-to-date news and progress reports, and the latest is in regards to the PS3 firmware update, 1.81. Yes indeed, it's available tomorrow!
The update will fix a few "small issues," including the RGB Full setting. Eric Lempel, Director of PlayStation Network Operations explains it this way:
"In 1.80 we added an option to the XMB under settings allowing you to choose between RGB Full and Limited. Basically if you are connecting your PS3 to your TV using an HDMI cable, and if your TV supports RGB full range, the picture quality may be improved when this option is set to Full. Some of you pointed out that the Full setting would sometimes revert back to Limited and 1.81 will address this issue. Please keep in mind that this setting is only effective when the PS3 is connected to a TV using an HDMI cable. You can download the update tomorrow from PlayStation.com or through your System Update option on the PS3 XMB."
He also mentions that they're "continually evaluating and improving PS2 software compatibility," but he didn't specify whether or not this update would include any compatibility updates. So when you log into the Network today, go ahead and download version 1.81; it'll be ready.