There has been near scientific consensus for some time (well before DNA analysis was available) that the Neanderthals were not human but were (on edit: at most) a closely related cousin. Having said that, there is still a great deal of controversy about the details. Dr. George Johnson has a nice little essay on it here if you are interested. http://www.txtwriter.com/Onscience/Articles/humanevolution.html
There has been a lot of speculation about how much interaction (socialization, conflict, interbreeding) there was between Neanderthals and modern man. The latest DNA evidence would suggest that if there was any interbreeding the Neanderthal genes are long gone. And the DNA evidence seems to rule out any possibility that Neanderthal was an ancestor of modern man (on edit) and confirm that Neantheral was a separate species and not a closely related cousin and thus not likely to have interbred.
This message has been edited by deerbreh, 07-06-2005 02:54 PM