The Fordyce spots on my lips just exploded out of nowhere about 2 months ago, after I'd had cheilitis already for about 11 months. I have no idea if they are simply a symptom in the progression of cheilitis, and if it was natural for them not to show up for many months and then suddenly to seem to be all over the place in my lips, or whether something I did in the autumn (some product I used, some vitamin that I did or didn't take, etc.) caused them to form in my lips.
Mine are pretty noticeable now. Tonight they are even more noticeable than they have ever been before - it's kind of freaky. They do look like whitehead pimples, deep in the lip surface (well, they are large and moderately deep in my lower lip, small and close to on the surface of my upper lip).
I don't want to worry about them, because my main concern is to stop my lip layers from peeling off each day and looking scabby and flailing about in the air when I eat in public, etc. Once my lip skin stays where it's supposed to, then I might worry about the white dots.
Fortunately, as a woman, I could probably use an opaque lipstick and cover most of my white spots up, at least on important occasions.
I also have a feeling that my fordyce spots will gradually fade, once my lips return to a healthy balance. I have never had these things in the first 41 years of my life, and I am adamant that the next xx years of my life will not be accompanied by weird-looking lips! :-)
They are apparently glands or ducts or something that get clogged, and 75% of the population has them in their skin layers when they are born, and a fair number of men get them on their penis/scrotum skin, but not too many people actually go on later in life to have the ducts get clogged up in their lip region and turn white.
By the way, the photos of fordyce spots on wikipedia are misleading and don't seem like good examples to me. I had to search around on the internet before I found photos of fordyce spots that more resemble what mine look like.
I agree with Chris that these are intimately connected to cheilitis. Don't worry, many of us have them.
If you are concerned, ask your doctor or dentist for his/her thoughts. Most will say that they are harmless and just a quirk of the body.