This would be a huge leap forward for joomla development.
If for each of the tables we could have the option to generate a RESTful resource, this would be a huge jump forward in allowing us to create mobile apps to accompany our joomla website. It would also make it possible to completely exchange the front end of your joomla site for a version build purely in AngularJS or a similar framework.
Here are some links to components trying to do a similar thing: