The Total Rewards “Diamond in a Day” option has been around for a while, but it is something that Caesars has kept rather quiet.  Finding out about the program was typically by word of mouth and still required asking at the Total Rewards desk to verify that what you heard was accurate for your casino since it did change from time to time and even from casino to casino.  Things are much more straight-forward now AND Caesars has even written about it in their blog.

Here is a link to their post.
http://lasvegasblog.harrahs.com/total-rewards/so-you-wanna-be-a-diamond-in-a-day/