A very good reference on qualitative analysis and CAQDAS is the book "Using Software in Qualitative Research: A Step-By-Step Guide" by Lewins and Silver (Sage Publication). Unfortunately it is perfectly up to date (first published in 2007 and reprinted in 2010), but it does an interesting comparison of the features and functions of seven fairly recent popular proprietary software: ATLAS.ti 5, HyperRESEARCH 2.6, MAXqda 2, QDA Miner 2.0, NVivo 7, Qualrus, and Transana 2.
I considered this briefly in my proposal. There are some terrific articles out there. Here are 2:
Hannes, K., Lockwood, C., & Pearson, A. (2010). A comparative analysis of three online appraisal instruments’ ability to assess validity in qualitative research. Qualitative Health Research, 20, 1736-1743. doi:10.1177/1049732310378656
James, P. T. (2012) “Clinical Doctors as Qualitative Researchers”: QDAS factors informing hospital research policy. The Internet Journal of Medical Informatics. 6(2), 1-13. doi:10.5580/2b29
There is a book recently released by Christina Silver and Ann Lewis with title "Using Software in Qualitative Research a step-by-step guide".It's a comparative study of different CAQDAS tools.