Ann Smarty at SearchEngineJounal has an insightful post on how to make sure that your site renders all elements well to the human user and the search spider.

An excerpt from the article:

* A search engine sees the page the way you want it to;
* A search engine is able to crawl your JavaScript and CSS elements (or maybe not if you don't want it to);
* A search engine sees your page elements in the correct order (if you, for example, want to make some page elements/links/text prominent, make sure they are the first a search engine sees when entering the page: the higher the page element, the more weight it carries).

The looking good part is interesting since it ensures that users always return to a site. I have been intrigued on how exactly a search spider gets to decide if the look and feel of the site is good. Organization of page elements is perhaps the strongest link for that. Also, intuitive layouts make a good impression on your first time visitors and surely they would like to check-in again.