If Los Bukis coming round every year with another chart-topper was comfortably predictable by this point, Luis Miguel scoring two chart-toppers in quick succession from his newest album is just as certain. It's becoming clear that the broad outline of Latin Pop history differs in significant ways from both the received and the actual histories of Anglophone pop; in the early 90s, Latin artists were still an-album-a-year entertainment machines, where much of the English-speaking world had already converted to the modern every-few-years release schedule, giving people plenty of time to soak up, get sick of, and maybe forget the last album before renewing the assault. Neither model is necessarily better than the other, but the compression of the first can make artistic growth seem almost instantaneous.
So I said about Luis Miguel's last album that it was the moment when he became not just a pop star, but an institution; but this one, Romance, was the biggest-selling album of his career, and, if Wikipedia is to be trusted, the biggest-selling Spanish-language album of all time. This song sounds it, expansively expensive, the first ballad since Julio Iglesias to bring in classical orchestration -- very few top-selling songs in the last hundred years have had oboe solos -- and a lush sense of space to Miguel's already beautifully sensitive singing. The song itself is just as splendidly ornate a love song; not perhaps as poetic as Iglesias' latter-day triumphs, but in the simplicity of its language and directness of its sentiment, a classic of the genre nevertheless.
And I do mean classic. Googling the lyrics inadvertently reveals that a lot of people have wanted to know what it means in English; and this sweet story on a cooking blog suggests a pop-cultural power I in my ignorance had been unaware of. The title means, literally, "I don't know you," but the saber/conocer distinction* makes that reading impossible; really, it's short for "no sé (que piensas) tú," or "I don't know what you think." The translation given at the link, "I don't know about you, but I etc." is exact even to its informality. Miguel is (once again) relating an obsessive, extravagant love, one which he's not sure is requited; he can't sleep, he's always going back over the night she "created with her kisses." That touch of vulnerability (but without self-pity) is a masterful summary of Miguel's vocal persona: he doesn't go in for the florid emotionality of a lot of Latin Pop singers of his generation and earlier, he's controlled and even, in his adulthood, a little reserved; which makes any vulnerable emotion that much more meaningful when it arrives.
*See also connaître/savoir, wissen/kennen, etc. A lot of languages make a distinction between knowing knowledge and knowing people.