Even supposed security “professionals” sometimes claim that Linux is no more secure than Windows and that it is just “security through obscurity”.

Tipping Point’s recent 3 day Pwn to own competition provides an interesting counter-example:

• Day 1: None of the OS’s were cracked
• Day 2: Mac was pwned when Safari went to load a hostile webpage
• Day 3: Vista was pwned when the latest version of Adobe Flash was installed
• But, Linux remained secure / uncompromised until the end of the competition

Yes, Vista does seem more secure than previous MS Windows versions, and yes Linux does sometimes require security patches. But Linux is inherently more secure due to its open source development and its design.