I guess you didn't RTFA.
We now have Sony's private keys that they use to sign the games you buy in the shops.
We can now sign our own homebrew demos/games/OS's using their keys and run them on unmodified PS3's as if they were signed by Sony.
Actually they haven't yet dug out these particular keys (keys used to sign games). What they have dug out are the keys used to sign executables. See [youtube]hcbaeKA2moE[/youtube]
As the presentations points out while the keys to sign actual Bluray games discs are not yet dug out, it's just a matter of time (and effort).
No firmware update can do anything to stop this without rendering all previously released titles unusable.
Firmware updates are to be expected but since there are ways to downgrade it won't be a problem, at least from homebrew point of view. However, it becomes a problem if you want to pirate games: New games will require a new, bugfixed firmware to run.
I predict emulation of new firmwares in the future, similar to that can be seen with PSP: The emulator will run on top of the hacked system, appearing as the latest unhacked system to the game, making it perfectly happy to run.