Been talking with Yoshihiro lately and got some "inside" information.
If you want any hope of playing homebrew on your 1.51. or 1.52 PSP, don't upgrade to 2.0.
He is currently working on a downgrader for 1.51 and 1.52. DO NOT UPDATE TO 2.0!
It appears to be a one shot deal. You won't be able to use the same method to run homebrew on your 1.51 or 1.52 because it HAS to be an update, or something along that lines. Looks like the hole might be in the updating process.
He has also put out a call for bricked PSPs. If your PSP has been bricked, and you cannot return it because it's out of waranty since you bought it online or some such, let us know. You can donate your PSP to "the cause" and, if you like, your name will be put into the NFO file when the utility is released.
If you're interested in donating your PSP, a bricked PSP, or just a 1.51/1.52 motherboard, get onto IRC and join #WAB on the irc.blackcats-games.com server. DO not join #WAB on EFNET if you'd like to help. It isn't the "Official" WAB channel. The Yoshihiro that is on EFNET is not the one we all know and love.