I recently saw an article lambasting the new custom of asking for a picture of the girl [and often of the boy as well] before meeting her [or him]. This is terrible, the article cried! How can people be so superficial and decide if they will go out with a girl based on a picture??!! This is also immodest. Look at a girl?? G-d forbid.
The answer is that we aren't frummer than Chazal. They required that the boy see the girl before marriage in order to ensure that he finds her attractive. What is wrong with sending a picture?! Superficial?? OF COURSE we are superficial. Hashem made us that way.... Men also look for other qualities but looks is usually high on the list and there is nothing wrong with that.
On the other hand I can see girls being very hurt when rejected just based on a picture. If they meet and he says no then she can attribute it to the fact that he didn't find her compatible. But if he rejects her picture she may take it that he thinks she is ugly. It is a grave sin to hurt a Bas Yisrael.
On the third hand - why not save them both time! If he doesn't find her pretty he will not marry her, so why not find out before the meeting??! If he rejects her the girl can tell herself that she is indeed pretty, but just not his "look". Or that he has poor taste. Or poor vision.
On the fourth hand, looks grow on people. Maybe the picture itself doesn't capture his fancy, but after getting to know her he will find her beautiful?!
On the fifth hand..... Well, who on earth has that many hands?! If the girl has five hands I don't think all that many boys would want to go out with her.
Not simple. But I don't believe that there is anything inherently wrong when asking to see a picture or 2 of a potential future spouse - not in halacha and not in mussar and avoda. There are bigger problems to fix before we tackle this "problem".
So it seems לעת עתה.