It is sort of a firmware update. One that should be done with the system in a very stable state (nothing running, internet off, antiviruses/firewalls disabled, everything in the system tray closed, etc.) just in case. It also requires that you have the battery attached and the AC plugged in.
It fixes all of the CPU throttling issues, so under most circumstances, the CPU can clock up to full speed.
eladbari wrote: i guess i can check the current version thru the bios itself.
You can check the current BIOS version by pressing the blue ThinkVantage key when you're in Windows. It will show the BIOS version as well as other information at the top of the ThinkVantage Toolbox window that will open.