Themes historically include CSS, images and some custom Smarty (*.tpl) files. However, increasingly, we are using modules. module menu, module logo, module breadcrumbs, etc.
So if you are developing a theme on server A, and you want to copy to server B, it's no longer just copying over the theme files, but also reconfiguring the modules.
This is time consuming and error-prone. Profiles are perfect for this, but building and maintaining profiles in wiki pages is time consuming. Now, thanks to the profile export, it becomes easier & faster.
In the future, we'll be looking into having this available as a text file in the theme package, a bit like System Configuration for preferences.
For now, go to tiki-admin.php?page=profiles -> Export
And on the new site, tiki-admin.php?page=profiles -> Advanced -> Profile tester
The code for this is r42346