i'm working on an e-commerce site where we list a few customer reviews about the particular product. we do not yet have the reviews tagged with any microdata. we do not want to publish the names of the reviewers. and we do not even know the review submission dates. we also do not collect star ratings. these are simply a backlog of testimonials we'd like to post. does it make sense to even tag the reviews with the other review microdata if we will be missing those three elements (date/reviewer/star rating)? or will it be a useless exercise? please advise. thanks in advance.
For microdata, Reviewer's name and the reviewed item name/description is required and mandatory. You can test your code with http://www.google.com/webmasters/tools/richsnippets If you don't want to reveal the real reviewer name just use Anonymous as reviewer name. If the property is filled even it's not real, it will be valid.
I would use the newer version of the Google Structured data testing tool to check your microdata. https://developers.google.com/webmasters/structured-data/testing-tool/ The new version will check and displays errors in your syntax