isnt it common knowledge when you have any modded console to NOT UPDATE its software (unless known devs tells you its ok to do so) otherwise you would get situations like this,
like guys you DO REALIZE that when you update a modded console you might never be able to get it modded again due to it maybe console manufacturer having patched the vulnerability (too late for the ps3 at this point but you never know) anti rollback checks, e-fuses etc.
so if you updated to 4.91 stop bitching about it and wait he already said its coming, nobody has said nothing is coming its not the end of the world like metldr2 came out or something, idk go touch some grass, listen to music, watch videos of people fixing up ps3s or something.
i for one still use 4.86 and see no reason to update any further even more so with the issues ive seen being discussed introduced with 4.90 about xmb layouts or xml or something like that (you can spoof firmware version you know)
EDIT also he and some other devs have atteched their names and reputations on this software, they dont wanna be known as the guys that brake ps3s due to releasing buggy software