I do not think there is anything illegal in voter swapping - it is is essence private persons persuading each other how to vote, e.g. by saying "I hate your politics so much that having learned that you will vote for tweedledum, I changed my mind and will vote for tweedledee" or "I respect you so much that having learned that you will vote for tweedledum, I changed my mind and will vot efor him as well."
This vote trading site is opertaional and shows no signs of illegality. http://www.winwincampaign.org/
In fact, the number of traders doubled since yesterday. Despite my earlier intention to vote for Gore, expressed earlier in this forum, I am considering trading my vote, since MD is a Gore-secure state.
wojtek