Certainly! PDFs or notes typed in MS Word can be imported into the 'Internals' folder and books etc. can be represented as externals. It's also possible to create attribute values for characteristics such as date published, so that you can use the NVivo query tool.

For further information regarding NVivo as a literature review tool, visit the following websites:

Conducting a Literature Review: A Puzzling Task
http://www.aare.edu.au/08pap/bee08127.pdf

Using NVivo as a Research Management Tool: a Case Narrative (NVivo 2)
http://www.cit.gu.edu.au/conferences/qualit2006/proceedings/PDFPapers/Bandara.pdf

Using NVivo for Your Literature Review (NVivo 2)
http://www.sdgassociates.com/mainframe.html