Since GMass uses the native Gmail Compose window as the basis for campaign creation, and since GMass allows you to copy/paste a list of addresses right into the To field, I thought it would be fun to see just how many email addresses the To field of the Compose window can hold. Is there a limit? Is there a connection between how many addresses Gmail will let you put in the Compose window and Gmail's actual email sending limits? Would the Gmail anti-spam pre-crime team detect that I've pasted thousands of email addresses into the To field and shut down my account before I even have the chance to hit Send (or the GMass button)?

Let's find out.