I'd hazard a guess that 0.1% of Java developers are aware that on some operating systems Object.wait() can awaken spuriously. Heck, it wasn't even in the Javadoc until 1.5. And don't even get me started on how you should handle an InterruptedException.

Most Java developers I know consider rolling your own multi-threading scheme about as wise as rolling your own cryptography, and just pretend notify/notifyAll/wait don't even exist.