Observations

I'd say that the bug and the idiom are independent. Having 'synchronized' without 'volatile' obviously was an idiocy, but why should I bother writing explicit synchronization incantations and runtime hints to initialize a singleton if the runtime already provides the mechanism. IBM (linked by upstartn) says the same thing:

Instead of double-checked locking, use the Initialize-on-demand Holder Class idiom, which provides lazy initialization, is thread-safe, and is faster and less confusing than double-checked locking[.]