v2.00 of the firmware has been released in Japan. If you copy the update files to the memory stick then you can apply it to other region PSPs. My PSP is a Japanese one anyway so I did it via network update.

Obviously don't update if you want to run homebrew stuff or want to run any in the future since they've done more security fixes.

One of the big features is that it's finally got a fairly decent web browser built in. It doesn't do Macromedia flash but I don't see that as too much of a problem. WPA-PSK with TKIP has been added as well.

There is a more complete list at IGN and it has a link to update files as well.