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Wakestaking involves maneuvering a wakeboard over a skateboarding course. It appears that competitors are yanked along a tow line and must safely but acrobatically pass the obstacles. Here are highlights from a recent competition in Cologne, Germany. http://www.waketheline.com/blog/ -via @Christopher Jobson
Wakeskating does not involve a wakeboard whatsoever.
This video is just plain ol' wakeboarding using a wynch.
Wakeskating involves using a board with a top surface similar to a skateboard. You wear shoes, and you are not strapped to the board.
This is an example of wakeskating: http://www.youtube.com/watch?v=iuCf_OT65fg
Gayest background music EVER! (and cranked to 12 in the mix).
Wakeskating is actually done using a wakeskate (it's like a wakeboard without bindings and the surface has more grip), it doesn't matter where. The video has highlights from both the wakeboarding and wakeskating parts of the competition.