If for some reason, the hotel's system doesn't show you as Platinum, you might run into some difficulties in receiving your platinum benefits, particularly overseas...
If I were you I'd request another card on-line and print out the temporary card there.
this is actually a very good advice.
I became plat last year and during my first stay as a Plat I was @ Westin in SYD. I discovered my status was showing as Gold when I tried to get into the Club Lounge. Lurker sorted it out, but it did take a day and couldnt get in the Club Lounge.