I use XTemplates in my frameowrk and i call the xtemplate file with a .xtpl extension. is there a way to get html syntax highlighting for .xtpl file types?

Yes. Go to: Tools -> Settings -> Associations and add xtpl extension to HTML or Smarty.

ok, now for the tough question, is there a way to create a new highlight config type? like i would want to copy the html exactly and then just add 1 rule so {whatever.text} would be colored different in a .xtpl file?

No, the only highlight-types that are available are the ones that are defined.

If you add xtpl into the list for Smarty highlighter, {whatever.text} will be colored differently