The games will be given away, not on a particular date, but when Cave Story+ has received a particular number of votes on the wishlist.
B̶r̶u̶n̶e̶l̶ ̶C̶h̶a̶r̶i̶t̶y̶ ̶G̶a̶m̶e̶ ̶J̶a̶m̶ ̶B̶u̶n̶d̶l̶e̶ ̶(̶I̶n̶d̶i̶e̶G̶a̶m̶e̶S̶t̶a̶n̶d̶)̶
̶T̶h̶e̶ ̶L̶a̶s̶t̶ ̶E̶x̶p̶r̶e̶s̶s̶
̶B̶a̶c̶k̶ ̶T̶o̶ ̶T̶h̶e̶ ̶F̶u̶t̶u̶r̶e̶:̶ ̶T̶h̶e̶ ̶G̶a̶m̶e̶
̶S̶a̶m̶ ̶&̶ ̶M̶a̶x̶ ̶S̶a̶v̶e̶ ̶T̶h̶e̶ ̶W̶o̶r̶l̶d̶
If you'd like to increase you chances of winning, tweet @nicalis (publisher of Cave Story+), @tyronerodriguez (founder of Nicalis) and/or @amaya_pixel (the creator of Cave Story) to let them know you'd like to see Cave Story+ on GOG and then post a link to your tweet as confirmation. A tweet will increase your chances by 5 (please only one tweet per @ account - don't spam), a response to your tweet (post confirmation) will raise them by 10.
As of the creation of this topic, the votes stand at 393.