For a great look at the effective, cost saving, voter empowering instant runoff voting system in San Francisco, check this out.
A few tidbits jump out at me from this:
"Significant tax savings: The City saved approximately $1.2 million by not having to administer runoff elections for four supervisorial districts"
"Winners received significantly higher percentage of total votes cast than winners in December runoffs; more voters had a say in who their supervisor is."
