> patching new vulnerabilities that allow jailbreaking has become a moot point.

I'm not sure how moot. A few iPhone jailbreaks have exploited vulnerabilities that would allow an attacker to execute arbitrary code on a user's device. So, while pretty handy for delivering a jailbreak payload, equally devastating were someone to decide they wanted to pilfer some address book content or damage system files.

I'd say patching such vulnerabilities is important, though the short-term jailbreak opportunities are nice. Apple also verifies a checksum of your OS installation to prevent you rolling back to old, vulnerable OS versions. So, legal or not, Apple isn't taking a nap on jailbreaking.