The nominating and voting statistics are available from http://www.thehugoawards.org/content/pdf/2015HugoStatistics.pdf -- this is the data that has been released by every Worldcon since before I began attending. It gives a clear understanding of the nomination and voting process, the number of nominations each work received, the vote counts at each stage, and the total number of nominators and voters.
The non-binding resolution passed this year regarded more specific nomination information. While Sasquan agreed to the resolution in good faith, unexpected complications have arisen in the process of trying to anonymize the data sufficiently for release -- including the need to comply with European data privacy laws. When we are satisfied that the data can be released in a form that protects the privacy of all nominators, it will be.In light of this generous offer from Jason Rennie--who works in medical research, and is therefore intimately familiar with utilizing data while maintaining the utmost confidentiality--it seems that little stands in the way of ensuring voter anonymity to Sasquan's satisfaction. I look forward to seeing the nomination data soon.