Potential topics to be researched in web services for PhD level

Dear all
I am a novice researcher who just enrolled to the PhD programme at UK
university. Previously, I intend to do on web extraction using XML for
Intranet environment, however, after having some sort discussion with
the supervisors, the focus has been shifted to the web services. I had
reviewed quite numbers of journals in web services, but due to the
mental block at the moment I failed to grasp the research gap in this
area. Can someone who is more experts assist me on the matter.
NHN