stripped driveshaft?

yeah, i know i got it right last spring, because i had the boat out about forty times since, and nothing at all was wrong with it until the last run of the season when the aforementioned incident occured. since the boat itself cost me only $1000 and performed great until the incident (motor still runs great), i wouldn't be too averse to dropping another grand to bring it back to how it was. i'd still feel like i got a bargain. thanks to everybody for their input, i'll let you know what the verdict is when it comes down.