The Dude is a supremely sublime album, the production is flawless and of course features that smooth sound that Q is so famous for. Q and Bruce Swedien developed a process which they called "acusonic" and this is the process that gives us that silky tone that we also hear with all of Q's later work.
Well, what about the songs, for me the best song on the entire album is Just Once, a song so powerfully moving that even now after some 24 years I feel my hairs stand on end. This was the album that gave us James Ingram and boy what a voice, One Hundred Ways as Rebecca pointed out is about the essence of true romance (the way it was meant to be, I guess), another beautiful song. Something Special is also superb with the wonderful Patti Austin.
The jazzier tunes, Razzamatazz, Ai No Corrida, Betch You Wouldn't Hurt Me (written by Stevie Wonder) are also top notch.
I have played this album, first on Vinyl way back in 1981 maybe 200 times or more and I simply never tire of it.
I guess another reason why this album means so much to me is that I was with someone very special at the time of it's release so I will always remember it by that too.
I believe that this album was/is the most nominated in Grammy History. Bravo Q, for me this is best album from you.