[jvolkman]

If the existence of a working unsanctioned client undermines the integrity of a system as prominent and security- and privacy-focused as iMessage proclaims to be, then that system has big problems.

Certainly this is not the first time some entity in the world has reverse-engineered iMessage; it's just the first time that it was publicized.

[ceejayoz]

Every system has holes that get discovered in time. Leaving those holes open is a different thing.

[danShumway]

This is also notable, because the technology that Beeper Mini is based on was public and available to potential attackers before Beeper Mini launched. Beeper didn't invent this, they contracted the developer and based the project off of their open Github repository.

Apple did leave the hole open; they left it open until it threatened their customer lock-in. Only at that point did they decide that it was a security risk.