Technology is wonderful and problematical in equal measures. Windows 7 is promoted as more secure than it's predecessors but still has it's vulnerabilities. Now Windows 8 is due to be launched in 2012 with the ability to run on Tablet PCs as well as laptops and desktop models, this too will no doubt have it's fair share of problems in the future.
It is true to state that no one Operating System is 100% secure and that individuals with ulterior motive will try to exploit weaknesses to gain accees to your confidential data.