Still holding out on Windows 7? Don't see any benefit to upgrading? Then, you might wanna give this post a read:
New data extracted from Microsoft's Security Intelligence Report shows that Windows 7 is seeing 5x less infection rates than Windows XP, and about half of what Windows Vista is seeing.
As in previous periods, infection rates for more recently released operating systems and service packs are consistently lower than earlier ones, for both client and server platforms. Windows 7 and Windows Server® 2008 R2, the most recently released Windows client and server versions, respectively, have the lowest infection rates on the chart.
One reason may be that 64-bit versions of Windows still appeal to a more technically savvy audience than their 32-bit counterparts, despite increasing sales of 64-bit Windows versions among the general computing population. Kernel Patch Protection (KPP), a feature of 64-bit versions of Windows that protects the kernel from unauthorized modification, may also contribute to the discrepancy by preventing certain types of malware from operating.
If you're still doubting the authenticity of the report, the below graph has shown that this is not due to Windows 7's infancy, showing there is no clear increase or decrease in infection rates, staying well below 4%.
You can read the Security Intelligence Report here (PDF): Link