Please note that after upgrading your firmware, you will be unable to return to previous versions. Currently firmware 1.51+ is unable to run homebrew applications, so please make sure you are fully aware of this prior to upgrading. With that said, US 2.00 has been posted on the official Playstation website.
Read about all of the new features at http://www.us.playstation.com/psp.as...SoftwareUpdate