"The Iowa statute limiting civil marriage to a union between a man and a woman violates the equal protection clause of the Iowa Constitution." And, "All justices concur."
The best part of the Iowa Supreme Court ruling? They don't amend their constitution via majority rule at the polls. It would also need to pass the Iowa House and Senate twice before going to voters. "Such an amendment requires the votes of a simple majority in both the Iowa House and Iowa Senate in two consecutive sessions, followed by a passing vote of the people of Iowa."
2012 is the earliest this decision could be overturned, and that's only if this current session were to vote on an amendment and pass it.