Actually, I had such a hard time finding anything OTHER THAN "(explicitly) CHRISTMAS" cards, that I had to look in seven most likely places to find enough "Happy Holidays" type cards to send out to some of my friends. I only failed to check Penney's and Dollar General. (JUB Card Exchange is only a small portion of what I send out.)
I have *NEVER* seen a Christmas card with a sentiment something like "Merry Christmas and Happy Holidays!" That would cover it all, wouldn't it? After all, there are AT LEAST two holidays in the immediate future, because New Year's happens everywhere, as well as Christmas. And, whether or not somebody actually celebrates or observes Christmas, it is STILL a holiday for almost everybody.
Gatherings and get-togethers, some of which are no doubt happening at this VERY MOMENT (early or mid Saturday evening in VIRTUALLY all of the United States and Canada, the two countries in this Hemisphere where I send my cards), and those could be argued to be holidays as well - or, at least, CERTAINLY "holiday get-togethers."
Because of this, "Happy Holidays" doesn't grate on me at all, unlike it does with some people. There is almost nobody anywhere that doesn't
"notice" at least two holidays at this time of the year, so it's more accurate, actually.
I cannot abide with Happy Hannukah, though - that phrase simply sounds TOO contrived. Though variations involve exchanges of gifts, Jews generally observe Hannukah in serious rituals (congruent with the importance of the history involved) in which a term like "joyous" is simply extraneous and certainly not the emphasis.
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But, most surprising, in all six places that I went to, I **DID NOT SEE EVEN ONE** card, of any kind, that said "Happy New Year" on it, or at least I don't remember seeing that PHRASE in print anywhere! (So, watch one of the guys from the JUB Card Exchange remind me that I sent them a card that included Happy New Year on it. If so, I give myself a well-deserved self-

!!.)
What the hell happened to Happy New Year? It's like it's vanished off the face of the Earth (on greeting cards).