Digital Cameras

Which camera is the best of the three?
Canon PowerShot SD870 IS (Black) Canon PowerShot SD1100IS 8MP Digital Camera with 3x Optical Image Stabilizer Zoom (Silver) Canon PowerShot SD850 IS 8.0 MP Digital IXUS camera with 4x optical zoom, which camera is the best of the three?
Depends on what you do with it [...]