why most of the pages of del.icio.us.com partially indexed?

[ujwal]

hi

i know the actual purpose of http://del.icio.us.com . and i have also heared that by finding the place in this site we can have better reference. but google
is not providing the catch to the pages in which the sites are listed and those pages are partially indexed . do google consider it as refference? or not.

could any one provide me with a proper answer

thanks and regards