Posted By EricFerguson:
Descriptions sell files Sean. People remember your pics because they have cool, interesting descriptions, especially if you incorporate keywords into them. I've bought photos before because the description was a dramatic monologue, and I just couldn't forget that photo as I looked through the others.
I've also see buyers complain about a lack of descriptions for editorial work where they want to put something in the caption. I'm convinced description-writing is part of the art of stock.
Unfortunately, that view is not based in reality. I can't remember when I cared about a generic description. Places, odd locations, curious objects, yes, I'd love a description. For a woman with a phone, I couldn't care less unless there is something really exciting about that particular woman (natural blonde! model released! now comes in nudes!).
While it's a good marketing tool, for linking multiple images of the same model or location or type, as a buyer the words "woman with phone" are ultimately useless and I don't bother with them.
Context is pretty important!
If someone has a big description, it may get linked through Google differently from the keywords, and boost views and possibly sales. If that's the reasoning, then let's say so, mmm?