If you are seriously considering the "slash and burn" security method, you might as well just take yourself completely offline. Yes, WordPress does have known and possibly unknown security holes, but so does MovableType, phpBB, the software that your host uses to manage their servers, PHP itself, your email application, your web browser, and even your entire operating system.
A word of advice, don't "slash and burn" to avoid security holes. You'll only make it harder on yourself, and you will eventually run into more security holes along the way. Instead, simply adapt, backup regularly, and take precautions.