It seems that the multiple frames of an animated GIF are no draw to search engine crawlers wheras image quality is now, and the reduced palate of a GIF is a drawback, so I've gone back to a J.PEG for my home page..
Jpegs and gifs are the most commonly used graphic formats on the web. Each has it's unique advantages and disadvantages. The material covered in this article will help you decide which format is more appropriate for your images. A general rule of thumb; use gifs for illustrations, clip art, and images with large areas of flat color, use jpgs for photographs and images with continuos tones.