I was a bit nervous when I first sent out our invitations with a couple not-so-traditional RSVP options:
I didn't know if people would be offended that I didn't provide a response card or if they wouldn't understand how to use the online option, but it has been a great success so far!
A big part of my decision to go with mywedding.com for my website hosting was (other than it being FREE) the fact that they had a great system for doing online RSVPs. This is what the guest sees when they check in:
I love that the site forces the guests to skip the more common mistakes that RSVP cards cause such as missing names and missing yes/ no responses. Even better, it forces them to include an email address so that I can follow up if I have any questions and makes them include the names of their guests and number of people in each party:
I did get one +1 guest response of First Name: "don't know," Last Name: "yet."
When I log in, I have an easy to navigate list of names and responses (that will export to Excel!). Most of my guests have even left nice comments for me to read in the comment form.
Oh, and... yes... we already have 22 yeses (original wedding goal was 50-75) and 0 noes in less than a week from sending invites out!!