We sent our STD's out in October 2010 for our Jan 2012 wedding as we wanted to give people as much time as possible to plan and save.
I am sending out our formal invitations in May 2011 and requesting them back by July 15, 2011 ( 6 months prior to our wedding in Mecico). I will give my final numbers to my Wedding Co-ordinator in August and that way anyone who hasnt committed to the wedding by that time, unfortunately won't be able to attend. I figure if people haven't figured out whether or not they are truly coming to our wedding by then, more then likely they aren't coming anyways. They have had almost a year to save since the STD's went out....so I figure thats plenty of time. Also my quotes have been out since February this year and the prices are slowly creaping up....so this also gives them the push they need to book, knowing if they dont book before July....they will loose the chance to come at all.
My first wedding was super stressful and busy until the last minute (back in 1999)...this I want to avoid at all costs. By doing it this way, I can complete all my DIY"s way before December knowing the exact amount of guests coming and there isnt a guessing game of who is coming and who isnt. Plus I wont have the last minute scramble that most of us will and have had because I will be done everything.
I hear about upset brides on here all the time bc people have not committed to the wedding or booked - and a lot of family and friends wait to the last minute. My way of doing it basically pushes them to book 5 months before the actual wedding. This not only gives them the opportunity to lock into better rates, but also makes it much easier on me.