A lot of times, when people look at pictures taken by a point-and-shoot vs an SLR, they know something is different, but just can't pinpoint exactly what it is...
It is the shallower depth of field...
See
http://www.istockphoto.com/article_view.php?ID=109
ABibleStudent said he likes pictures with large apertures and black-and-white. Well... I don't have many photographs like that, but I have some close-ups that I think are very good: