I'm not aware of any similar program on Princess, but you might want to check out the wine tasting event that usually takes place on the first day at sea if you enjoy wine. Here's how it works:
>> You register in the atrium on the morning of the event. There's a $5 charge, billed to your on-board account. The tasting itself takes place in the afternoon.
>> If you order a bottle of wine at the end of the wine tasting, you receive a credit of $5 toward the price of the bottle of wine. The bottle can be any wine from the ship's wine list, and need not be one of the wines sampled at the tasting. The staff will serve the bottle of wine in the dining room on the evening of your choice. Thus, you essentially get the tasting for free.
The tasting normally includes two white wines, two red wines, and a sparkling wine. The maitre d' and the head waiters provide descriptions of the wines, etc., during the tasting, and they are very knowledgeable.
I have generally found prices on Princess's wine list to be comparable to or perhaps slightly less than those of discount liquor stores here in Massachusetts for comparable wines. You should be aware, however, that there are not many "cheap" wines on the shipboard wine list. I recommend ordering a bottle each at the tasting, then ordering additional as you go. This will eliminate any pressure to finish the bottle each evening, since the dining room staff will gladly recork the bottle and serve the remainder on another evening.
If you want to bring your own wine aboard (or if you receive a bottle from your travel agent), Princess will serve it for a $5 per bottle corkage charge (also billed to your onboard account).