I was thinking about this earlier. Could the reason be that the NA 2.0 Update is delayed because sony found a mistake in that loading the JP firmware on a US psp does something to the device to get around there security patches. I dont know what but something is the region settings causes glitch. I have heard ppl that have updated have crashed their psps in the webbrowser.
Though you would think Sony would do scenrio testing, verifing all possible installs of the firmware. If the firmware was never suppose to be used on a US psp wouldnt they put measures in to halt install of it? Sony was quick to say that your warrenty would be void if you update. Would this be them tring to blow smoke and stop wide spread of teh JP update before the NA update was released. And they couldnt patch the NA update in time for its release so they are silent tring to get a fix. Just a thought.