Not sure if anyone else has noticed it or not but I've found two different fonts used on the back of the @2009 slot cards from Harrah's. So far I've only found it on the Gold and Diamond levels, not the Platinum. Plus I have not seen both fonts on cards with the signature strip, just the original font.

The easiest way to spot the difference is by looking at the bottom line of text on the reverse, especially the "9" in the phone number near the middle. On the earlier cards and one variation of the @2009 cards the nine has a more rounded tail. On the newer cards with the new font the nine has a more straighter tail. It's pretty easy to spot when you have both cards side by side. The fonts appear to be slightly different in size as well and other letters or numbers have slight differences, like the zeros are more rounded in the newer font, etc.

In the scan below, the top card is the original font and the bottom card is the newer font.
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