There is a big misconception out there that to make a site rank well in search engines, you need to make your site look ugly. SEO (search engine optimization) does not have to look ugly. Yes, having a lot of text and hyperlinking your content, where it makes sense, is important SEO factors, but it doesn't have to look ugly.
A Google Webmasters Help thread has a webmaster who said that the SEO process is "killing the look" of his site. It doesn't have to. You can use CSS, graphics and other elements to make your site look pretty and still rank well. As long as you make sure to place enough text on the page and format it properly, it still have look great.
If anyone tells you, especially your designer, that the suggested SEO changes will look ugly, so don't do it. They are wrong. The designer should be able to be creative enough to come up with a way to get the SEO requirements in the new design and still make it look professional and pretty. It is done every day and it is done successfully and professionally.
Forum discussion at Google Webmaster Help.
This article was written earlier this week and scheduled to go live April 9th.