He has not, and the data collected via user-compare is generated solely via data collected from the API and almost exclusively used for SPI http://en.wikipedia.org/wiki/Wikipedia:Sockpuppet_investigations where gathering and analyzing this data is standard practice. Had I been using non-public data (anything generated from the sql databases that normal users do not have access to) I would agree that there may be privacy issues, however every piece of data that is used for that tool comes from the en.wikipedia.org API.
Betacommand