ImageReady 2.0, which is packaged and installed with 5.5, is Adobe's nod in the direction of the Web. Whilst you can optimise images for the web directly in 5.5 (using the File > Save for Web option) ImageReady allows you to slice up the image into smaller parts, insert rollovers (ImageReady will write the JavaScript and HTML), animate your GIFS and generally do the same things as Fireworks 3.0.
Why not have these two programs as one? Photoshop 6 takes a step in this direction by allowing you to add you slices and optimisation settings. But ImageReady is still packaged individually and used to create rollovers and animations. Confusing, huh?
Checkout the Adobe site for more!
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