Hmmm, what to do, what to do.

Personally I'd keep it all to myself, then sell it when the method is no longer effective to squeeze a bit more money out of it.

However, if you are making say $10k per month with the system, why not bring on board a few partners that would be willing to split the profit with you indefinitely? Sure trust would be a factor, but then again if you sell your method who's to say that it won't be shared like every other method that's ever been sold online....