As this excerpt from a recent JESSE message by Sheila Webber (Senior Lecturer, Department of Information Studies, University of Sheffield) shows, the view of issues surrounding online Ph.D. programs can be quite different accoss the big pond. (You’ll recall that the Robert Gordon University is about to offer an online Ph.D. in addition to its six online master’s degrees.)
Firstly, the information (or an advertisement ;-) Sheffield University Department of Information Studies, in the UK, has options for our PhD programme—”Joint location” (full time—expected to complete the degree in normal 3 years, one year must be spent at Sheffield) and—"Remote location" (part time—there must be at least one face-to-face meeting per year, and there are conditions laid down for communication). At the moment, for example I am supervising one remote location student (an Irish librarian investigating Continuing Professional Development needs of solo librarians).
See: http://www.shef.ac.uk/postgraduate/research/away (info on studying away from Sheffield)
http://www.shef.ac.uk/postgraduate/research (info on research degrees at Sheffield)
http://www.shef.ac.uk/is/research/resappn.html (info on my Dept.—n.b. the detailed menu for more applications info, on the right of this page, including the format of the research proposal)
Sheffield is a research-led university and the Department of Information Studies has obtained the top possible score in all three of the UK’s Research Assessment Exercises (one of an exclusive band of Departments in any subject area to have done this). (OK, ad almost over.)
I *think* that British PhD programmes differ from North American ones in that the instructional component of British PhDs is less, with focus on developing and investigating your own research question throughout the three years. For full-time PhDs (on campus or joint location) there is a Research Training programme of credit-bearing modules (which most students would take during year 1). Part-time students do not have to take this programme. . . .
Finding people (in addition to your supervisor) to discuss your research with will obviously help you on your personal research journey, particularly people using the same research approach. For, e.g., some types of IR research there is a thriving research community within LIS and sometimes within individual Departments. For others (given the broad spectrum of research approaches which are employed across the whole LIS spectrum) you ideally would want to seek out fellow researchers elsewhere, anyway. Being a distance learner might push/encourage you to get "out there" that bit earlier. From that perspective, if you are able to identify a research community for that research approach internationally and engage in virtual and preferably face to face discussion (at conferences and seminars), this may exteremely valuable.
My feelings are that a mature PhD student may actually have the confidence to engage in this dialogue at an earlier stage, and also have have more command of resources (possibly!) to fund (or get funding for) attending research seminars etc. Also, having to explain and justify your research to interested fellow-practitioners back home can be very valuable & motivating. . . .