We reported 2 days ago that Apple will be releasing a firmware update soon to fix the PDF exploit through which JailbreakMe could jailbreak the phone. The firmware has just been released moments ago and can be downloaded through the links below. If you connect your device to your computer and run iTunes you should get the download message anyway. If you would like to keep your phone jailbroken, you shouldn’t be updating the firmware right now.
Official download links by Apple