Trello.members.get
is an asynchronous function (i.e. it takes a callback instead of returning a value); you'll need to use a callback if you want to do something with the data that it fetches.
If you change getMemberID
to take a callback
...
getMemberID: function(callback) {
Trello.members.get("me", function(member){
callback(member.id);
});
}
...
... then you could do something like this:
TrelloConnect.getMemberId(function(id){
new Board(id);
});