Good looking furniture, fabrics, and lighting are certainly essential, but the importance of accessories, art, plants, etc., cannot be underestimated. Styling is soo important in making a room look both lived in (rather than just a bunch of furniture gathered together) and giving it personality.
These three desks are taken to the next level by their wonderful styling. Styling takes a functional piece and allows it to add to the overall look and feel of a room. What if all of these desks just had a blotter and some pens? Their visual power would be much less effective.
In all three, note the use of books, plants (fresh flowers, architectural branch arrangements, etc), lighting (the top piece uses two lamps to great effect-- not an obvious idea though), art, and actual desk necessities (writing utensils, paper goods, and organizational things) made to look appealing.
The arrangement of such items is also key-- the books are both stacked and upright, objects are grouped together, art is both hung and propped, pieces are layered in front of and behind each other...
At top, Michael Bastian's apartment (the whole thing is great.) (Also, no coincidence that someone in fashion would have a well-styled apartment, styling uses many of the same principles in fashion and interiors. See more about his fashion looks here.)
Third, David Hicks.