As you can see, Feed API for Drupal is a wee bit buggy when it comes to importing content from Delicious.
I wonder if this is due to invalid feed content actually coming out of delicious? I suspect this because feed API uses built in PHP functions for parsing XML and feeds, and it seems to work well for everything else.
In Jan, we should build a new FLOWS delicious parser that has permission to POST to culturing via services (or even to wagn).