Microsoft's been doing the talking, Sony is doing the walking. PlayStation 3 is the console for those that value choice. From a standard three-pronged power cord to a standard hard drive bay, Sony's hardware is compatible with a vast range of products, including additional operating systems (e.g., Linux).
Already own a USB headset? What about a web cam? As Microsoft forces us to buy into -- often inferior -- proprietary devices, Sony welcomes us to use those peripherals we might already have lying around. Bravo!
PS3 delights vs. PS3 annoyances
Wii delights vs. Wii annoyances
Xbox 360 delights vs. Xbox 360 annoyances