Yes, I know, Firefox 2 results are almost 1-to-1 like IE 7.

“Nearest Neighbour” is the WORST algorithm! MS Paint uses this algorithm for resizing. It is so bad, that it had to die in Pentium times, I can’t understand why there STILL EXISTS software which uses this stupid algorithm in our modern world.

Bicubic Resizing vs Bilinear
[nickyguides.digital-digest.com]

BTW, Adobe Photoshop also have those options in “Image Size” dialog window. Here is explanation from Adobe:

• Nearest Neighbor is the most basic, and it’s very fast: To create a new pixel, Photoshop simply looks at the pixel next to it and copies its value. Unfortunately, the results are usually lousy unless the image is made of colored lines or shapes (like an image from Illustrator or FreeHand), but it’s often useful for preserving the readability of screen shots.
• Bilinear is slightly more complex and produces somewhat better quality: the program sets the color or gray value of each pixel according to the pixels surrounding it. Some pictures can be upsampled pretty well with bilinear interpolation. But we usually use one of the bicubic options instead.
• Bicubic interpolation creates better effects than Nearest Neighbor or Bilinear, but takes longer. Like Bilinear, it looks at surrounding pixels, but the equation it uses is much more complex and calculation intensive, producing smoother tonal gradations.
• Bicubic Smoother is a new interpolation method specifically designed for upsampling. As its name suggests, it gives a smoother result that handles subsequent sharpening better than Bicubic sampling.
• Bicubic Sharper is another new interpolation method, only this time designed for downsampling. It does a better job of preserving detail than does Bicubic.

Bicubic:
“It preserves fine detail better than the predominant bilinear algorithm.”

Bilinear:
“…is rather accurate until the scaling of the texture gets below half or above double the original size of the texture.”