It's interesting that Rust is starting to use the same version-naming scheme that ECMAScript and Ubuntu did, being year-based. Personally I think Ubuntu's naming scheme and release schedule is the best, releasing $N times per year and naming it $YY.$N, where N is the same each year. This has a host of benefits: it's obvious how old any given version is, it's predictable when a new version will be released, it helps prevent development from stalling for any reason, especially unnecessary-rewrites and way-too-big-features, and more!