Lazy Var vs Let

This is the latest scripture from the Xcode 6.3 Beta / Swift 1.2 release notes:

let constants have been generalized to no longer require immediate
initialization. The new rule is that a let constant must be
initialized before use (like a var), and that it may only be
initialized: not reassigned or mutated after initialization.

This enables patterns like:

let x: SomeThing
if condition {
    x = foo()
} else {
    x = bar()
}

use(x)

which formerly required the use of a var, even though there is no
mutation taking place. (16181314)

Evidently you were not the only person frustrated by this.