Ranked choice doesn't always get the correct result, but it's a lot closer than a simple vote.
"If no candidate receives a majority, the candidate with the fewest first choices is eliminated and voters who liked that candidate the best have their ballots instantly counted for their second choice."
- http://www.rcvmaine.com/how_does_ranked_choice_voting_work
Condorcet IRV seems a reasonable choice, in that it's relatively easy to explain to people (compare to beatpath, for example).
I think all the discussion about the merits of different methods is just so much bikeshedding. It might matter, but it's far more important to pick _something_ than to stick with plurality!
In that spirit, I am totally in support of Maine's choice to go with IRV, even with its warts.
Instant runoff, among other things, keeps major parties on their toes and more responsive to the electorate's needs, since if voters are sufficiently angry they have a realistic option of putting a minority/third party in power.