The number one issue for me is lack of web development in the field of Geographic Information Systems. You can learn how to build a good website or how to add GIS to web pages, but there is little to no information that includes both, building a Geographic Information Systems Website from the ground up while maintaining the separation of content, style, and functionality.

I use the JavaScript API from www.esri.com at need to have more information available to ensure I am building a solid application.