There's no such thing as a 'slim' or 'executive' Nexus 7. Those are just being used to describe the cases. There are only two models of the Nexus 7. The original model which was introduced last year and the new 2013 model which was introduced a few weeks ago. That's it. If you have a 1920 x 1200 display it is the new 2013 model and if you have a 1280 x 800 display then it is the original. Another way to tell is if you have the soft touch dimpled back with 'Nexus' running short-ways from side to side then it is the original. If the 'Nexus' logo is running long-ways on the tablet back then it is the new, 2013 model.
Hope this helps.