The Fraser Institute recently published a report, Proportional Representation in Practice: An International Comparison of Ballots and Voting Rules, that is very interesting.
Here's the intro:
"Proportional Representation in Practice: An International Comparison of Ballots and Voting Rules finds that any replacement of B.C.’s current First-Past-The-Post electoral system with a form of Proportional Representation will require trade-offs, an understanding of the impact that such changes will have on the way votes are counted and what impact the new system may have on the legislature and the party system."