i'm doing an ma in librarianship in the uk now. i applied to two school and got into one, though technically i didn't meet either school's 3.0 gpa requirement for admission as i attended a non-traditional liberal arts college in the us where we received narrative evaluations instead of grades, hence graduating with no gpa. neither uni here had experience in dealing with that. oddly, the school with the better academic reputation was the one that offered me admission, while the other was more strict about sticking to their guidelines.
there is a reciprocal agreement between the ala and cilip stating that a library degree accredited by either will be good for employment in both countries. though since i've not studied library science in the us, i can't say for certain, my impression is that the course in the uk assumes more knowledge of how a library operates due to most students having a year of practical experience going in. i don't think the degree is of dubious merit at all. honestly, library science is not rocket science and the lecturers here have said as much. if you've completed a ba, you should be able to handle the coursework fairly easily. all library science degrees seem to hold pretty equal weight.