SEO and Javascript

Hi

I have created a script that can change text when roll over a link, all i want to know is that will this method seen by search engines or not ?
I mean the texts that will change are in html body, so will it help SEO because instead of using image rollovers i am using text roll overs ?

you can see the example here :
http://www.datisdesign.com
if you roll over the icons on orange area, the texts above it will change

If you look at the page source you will see this part :

<ul  id="top_services">
<li id="web_design" onMouseOver="changetext('main_content_header','Website Design','main_content_text','Nowadays having a website is like having a powerful tool for introducing your skills, abilities, etc. Doesn&acute;t matter if you are an individual or a huge company. Here we guarantee efficiency together with beauty in designing your web pages, giving a pleasure to your mind while viewing the web site.')" onMouseOut="changetext('main_content_header','Designing For Communicating','main_content_text','Communicating plays an important role in today&acute;s world. In this regard internet has gained a very powerful position. Gradually, more and more web sites have appeared on the net, among which only some are able to present the required and expected functions, hence the ability to communicate properly with the users and efficiency are considered as two prominent aspects of a web site. Our main goal here in Datis Design is to satisfy all your needs and expectations in designing your website while using the latest web standards.')"><a href="#" title="Website Design">Web site Design</a></li>
<li id="multimedia_design" onMouseOver="changetext('main_content_header','Multimedia Design','main_content_text','Preparing multimedia presentations for showing your abilities and skills is another useful way for improving and expanding your business.')" onMouseOut="changetext('main_content_header','Designing For Communicating','main_content_text','Communicating plays an important role in today&acute;s world. In this regard internet has gained a very powerful position. Gradually, more and more web sites have appeared on the net, among which only some are able to present the required and expected functions, hence the ability to communicate properly with the users and efficiency are considered as two prominent aspects of a web site. Our main goal here in Datis Design is to satisfy all your needs and expectations in designing your website while using the latest web standards.')"><a href="#" title="Multimedia Design">Multimedia Design</a></li>
<li id="threed_design" onMouseOver="changetext('main_content_header','3D Design','main_content_text','We can also help you to introduce your services, goods, etc by 3D designing here in Datis Design.')" onMouseOut="changetext('main_content_header','Designing For Communicating','main_content_text','Communicating plays an important role in today&acute;s world. In this regard internet has gained a very powerful position. Gradually, more and more web sites have appeared on the net, among which only some are able to present the required and expected functions, hence the ability to communicate properly with the users and efficiency are considered as two prominent aspects of a web site. Our main goal here in Datis Design is to satisfy all your needs and expectations in designing your website while using the latest web standards.')"><a href="#" title="3D Design">3D Design</a></li>
</ul> 

I want to know that search engines can see this change text effect or not ? can they see the texts that are included in <li> tags ?

regards