[MrPedantic]

This may be one of those happy occasions where I can agree with everyone.

I would look at it as follows:

1. Status (long u) is the correct plural in Latin (4th decl., as Bob says, rather than 2nd decl.)

2. Status (long u) is a "rare" (OED) plural in English. (And rightly so: I challenge anyone to work it into a conversation without attracting strange looks.)

3. Stati is not the correct plural in Latin, but is quite common in English.

4. Statuses is not the correct plural in Latin, but is a valid anglicised plural, and also the most common in English.

I feel a little sorry for #3. I wonder whether a convoluted case might be made for it: perhaps on the grounds that we are now so accustomed to -i as a plural for any remotely Latin-looking word that ends in -us, that it's almost a valid English plural in itself. (This would also let "octopi" off the hook.)

MrP