First off, let me detach you from the notion that you can dine at the Olympic only once during a cruise. Please note my review of the M from last year (Alex Skabry). Moreover, I am just off the ship and dined there three times during the seven night cruise.
Arrive early on the ship, go directly to the Rendevous Lounge and simply ask for multiple reservations. And then, be persistent and call daily to find out if there have been cancellations.
The menu is the same nightly, and insofar as my fading memory serves has been unchanged since 2001. The quality of the food remains quite high- especially for such items like the goat cheese souffle, Steak Diane and Chocolate Souffle. The service seems to have actually gotten better, which says a great deal. Be sure Erdal, Savas, Petar or Alex takes care of you. Especially- have Alex prepare the Diane. (He's one of the longest tenured servers in the room.)
Hope this helps.
> I'm sailing on the Millenium soon and was wondering about the
> food in the Olympic. Does anyone have menus from that
> restaurant? Since you're meant to only dine there once per
> cruise, is the menu the same each night? If not, which is the
> best night?