Firmware 1.82 is now available to download for the PlayStation 3. The update enables the playback of AVC High Profile (H.264/MPEG-4) files, as detailed by PlayStation Network Operations Director Eric Lampel. You can update your console using the Network Update feature via the Network Settings on by using a External Storage Media.
The regional websites have not been updated so far but logging on to your PS3 should inform you of the update, providing you are connected to the Internet.