If you are developing a website for mobile users then its extremely important that your site be mobile friendly on all levels.
Delivering your content to mobile devices is not very difficult as long as you follow basic xhtml guidelines as outlined by the W3C organization. User experience once upon landing on your website will either be favorable or a complete turn off, in which the later of the two meaning no repeat visitor.

My best tips to you in this area for being successful is how you develop your site in regards to your content, keep images very low in size and bytes, and only use text links for advertising purposes.

Since there are a number of different screen sizes, from laptops to cellphones I build separate area for my mobile users like CNN and Facebook do. Most mobile internet devices do not have access to high speed bandwidth, as well many times cost can be a factor with carriers charging an arm and a leg for transfer.
The link below covers the basic guidelines that you should follow,

Mobile Web Best Practices 1.0
http://www.w3.org/TR/mobile-bp/

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