Yes, OS X (and any other Unix like system you may care to mention, including android.) is more secure and stable than Windows. However, the word 'more' implies a scale! To get near to impervious, you need to be looking at a hardened OS like something running SELinux or AppArmour for example.
Even if you accuse Apple of not reacting quickly enough to a problem that existed from the end of last year, that's nothing new. Apple has a reputation for not releasing patches very quickly. If you want an example of a quick patch for a reported vulnerability, try Googling 'Wicd privilege escalation".