It has been said alot around the internet that Search Engines have trouble crawling Content management systems like Joomla ?! This of course is the same with any Dynamic URL site, for example forums have dynamic url's.

There are always solutions to this with some great add-on's or extensions, Joomla it's self has something called SEF (search engine friendly) which will organize your urls into readable addresses for search engine, of course you can go one step further and install one of the following

Open SEF - Link to follow

JoomSEF - Link to follow

SEF404 - link to follow

These Extensions will Rewrite Joomla Urls so that its readable to Humans and SE's , Instead of the normal URL's created by joomla you will have nice Keyword Rich addresses, For example :

http://www.joomlaxtreme/content/blogcategory/0/33/

Above is the example of Normal SEF URL's but with the 2 components listed above your Urls can look like this :

http://www.joomlaxtreme.com/joomla-/portfolio.html

These are Keyword URLs, so everytime you post something new the URL will contain the title of the page thats been created.