Ah yes, the infamous discussion.
Ignore this thread if you wish, I just thought I'd post my thoughts which got me thinking on the topic.

int main()
7 letters
return 0;
6 letters and a number, 7 keys

A total of 14 characters for int main / return 0.

void main()
8 letters
return;
6 letters

A total of 14 characters.

int main()
7 again - not returning anything ( small program )

void main
8 again - not returning anything ( small program )

It actually isn't harder to say int main, it's equal when returning something, and easier when not. It's also safer.

Void main, is truly wrong.