Well, these things are good to know, you know. Anyway Blizzard Entertainment uncovers the system requirements revealed for the forthcoming add-on World of Warcraft: Cataclysm.

Here are the minimum specs:

• OS: Windows XP 32bit (SP3), Windows XP 64bit (SP2), Windows Vista 32bit (SP1), Windows Vista 64bit (SP1)
• Processor: Intel Pentium 4 1.3 GHz or AMD Athlon XP 1500
• Memory: 1GB or more of RAM * Video: NVIDIA GeForce FX or ATI Radeon 9500 video card or better
• Sound: DirectX-compatible sound card or motherboard sound capability
• HDD: 25 GB free hard drive space
• A keyboard and mouse are required. Input devices other than a mouse and keyboard are not supported
• You must have an active broadband Internet connection to play

And here are the recommended specs:

• OS: Windows XP 32bit (SP3), Windows XP 64bit (SP2), Windows Vista 32bit (SP1), Windows Vista 64bit (SP1) Windows 7
• Processor: Dual-core processor, such as the Intel Pentium D or AMD Athlon 64 X2
• Memory: 2 GB RAM (2 GB for Vista users)
• Video: 3D graphics processor with Vertex and Pixel Shader capability with 256 MB NVIDIA GeForce 8600 or ATI Radeon
• Sound: 2600 or better DirectX-compatible sound card or motherboard sound capability
• Broadband Internet connection
• Multi-button mouse with scroll wheel recommended

World of Warcraft: Cataclysm is set to launch on December 7. And do take a look at Blizzard's recently released cinematic for the game (if you haven't done so already).

Source.