I personally don't know if the keys can be updated without upgrading the whole PS3 software. But unless you are staying on 3.41 for a specific reason, you may just want to upgrade to one of the 3.55cfw's.
From my experience, the 3.55kmeaw cfw (just using that one as a reference as I didn't use the others) did everything the 3.41 with hermes dongle did. But even with 3.55 there will still be an issue with the keys needing updating at some point. At least if you update to one of the 3.55s it should help with some blu-ray movies. If someone does know how to update the keys, I would also love to know how it's done.
You will probably have to wait until the Hacks fully understand all aspects of the more current firmwares unfortunately. when they decrypt newer firmwares that might lead to extracting the keys for the BD player. the only other option is dumping the nand and other roms and comparing it with the decrypted firmware in existence in hopes it will lead to better understanding of how the update works on the DB player. Good luck with that little project. If we are lucky the BD drive emulator rumor in the works may lead to a cure for the Bluray Itch.
Blu-ray keys ehh? If you talking about the drive it self I dont know if there's a BD key that restricts it. But one thing for sure, this BD movies that requires update or so is all about the built-in BD Player software by Sony. If an instance that Showtime can do this (not far from reality, it just need some time) then you can forget about this new firmware requirement issues.