Question on Bhagavad Gita and Caste

When Krishna talks to Arjuna about committing to his duty in devotion, he refers to his caste of being a Kshatriya. The Kshatriya Caste in the Mahabharata book is explained in some detail (eg. never turn your back on battle) meaning each caste has a set of rules one must follow to obtain the higher planets.

In modern society the caste system has died down especially in the west, so when we refer to duty is that towards our day to day job or do we still follow some sort of caste even though its not pushed by modern society?