psp-hacks has a full package for the 2.5/2.6---->1.5 downgrade..
no need to troll for firmware dumps.
after that downgrade,there is also a new 1.5-1.00 downgrade, this will lead to the ability to run custom firmware as 1.0 has no security checks and can run unsigned eboots.(no reason to downgradde to 1.00 just yet, unless your a dev)
also just announced on pspupdates that they have decrypted the 2.7 firmware. so this could lead to finding an exploit for those unforuntate enough to have bought or upgraded to a 2.7
been a crazy week in the PSP scene..
theyve just been cracking that thing open like a nut