Octopuses vs. Octopi

Following the announcement earlier this year of Seattle's new hockey team, the Kraken, what's the most correct way to write the plural of "octopus"?

1. octopodes

2. octopuses

3. octopi

4. octopus

The answer is . . . "octopuses." "Octopi" is a supposed Latin plural, but "octopus" is of Greek origin. While "octopi" has become acceptable as a variant through persistent misuse, the correct foreign plural is "octopodes." This word would be extremely pedantic to use, though, like calling a single piece of writing on a wall a “graffito” instead of “graffiti.”