I just wanted to point out that many of the people who say the fonts are fuzzier are using the san-serif font. I use the serif font myself, but looked at the san-serif font after installing 3.0.3. I does look fuzzier to me. Don't forget that the update page says, "After installing the update, please share your feedback with us at
kindle-response@amazon.com. We look forward to hearing about your experience and appreciate your feedback." I'd encourage you to email them.
Although in the past, with some various issues, I've felt that people were being overly nit-picky, I must say that the san-serif font really does look worse to me. I don't use that font, but I still want the option to use it (and have it look good) and I feel for the people who do use it and are upset.