This sounds like a simple question. I will say like many other developers/architects/consultants - "It depends..."
Bottom line AJAX is bad for SEO!
For publicly facing company websites, were SEO important, stick with
the server side scripting such as ASP.NET, PHP, Ruby on Rails and
others.
I am not mentioning static HTML pages here since medium and big size companies most likely will have data driven web site.
If you are building Line of Service business application AJAX will only make your application better.
Do not think twice learn it well and use it.
If you absolutely have to use AJAX follow "Unobtrusive JavaScript" pattern.
AJAX is great tool when used for
proper application types.
Here is my prediction -> 3 years from now Search engines will learn to understand and properly index and rank RIA/AJAX/FLASH/Silverlight/Flex/Put your faviorite client side technology here. Until then ...
AJAX and SEO: How to have an SEO Friendly AJAX website using jquery
http://www.davidpirek.com/blog.aspx?n=AJAX-and-SEO:-How-to-have-an-SEO-Friendly-AJAX-website-using-jqueryhttp://www.seomoz.org/crawl-test12 More SEO Tips for 2007
http://www.seochat.com/c/a/Search-Engine-Optimization-Help/12-More-SEO-Tips-for-2007/SEO Myths
http://www.seochat.com/c/a/Search-Engine-Optimization-Help/SEO-Myths/3/SEO for AJAX
http://www.johnon.com/270/seo-for-ajax.html
AJAX, Web 2.0 and SEO
http://www.hybrid6.com/webgeek/2007/01/ajax-web-20-and-seo.phpWeb 2.0 Technologies and Search Visibility
http://searchenginewatch.com/showPage.html?page=3624222Unobtrusive JavaScript
http://en.wikipedia.org/wiki/Unobtrusive_JavaScriptCSS, AJAX, Web 2.0 & Search Engines
http://www.seroundtable.com/archives/006889.htmlSearch engine optimization
http://en.wikipedia.org/wiki/Search_engine_optimization
