alt Hacker NewsIt's been obvious for a while now that root-of-trust schemes create juicy targets, and that juicy targets attract all sorts of bad behavior that wouldn't be economical if we used a web-of-trust.
Building a web-of-trust scheme that works might not be easy, but also it's not like we've been trying exceptionally hard lately either.
Web-of-trust doesn't work. Even before the PGP web-of-trust broke down several years ago, analyses of how the web-of-trust actually ended up working out showed that it basically boils back down to CAs: people rely on a few highly central keys to do most of the signing rather than signing keys themselves, and these keys effectively function like CAs.
The broader issue is that users don't want to (and probably don't have the ability to) actually make any trust decisions; they much prefer to delegate all of the decisions on trustworthiness to somebody else. The PKI root CA system does have its flaws, but on the whole, I suspect that people like Mozilla are better stewards as to whether or not the person vouching for somebody else is trustworthy than the average or even the above-average user.