For reference, the DS-160 (form to book a visa appointment) question is as follows (for an E3 visa at least, unsure if this is different for different visa classes):
Do you have a social media presence? Select from the list below each social media platform you have
used within the last five years. In the space next to the platform’s name, enter the username or
handle you have used on that platform. Please do not provide your passwords. If you have used more
than one platform or more than one username or handle on a single platform, click the 'Add Another'
button to list each one separately. If you have not used any of the listed social media platforms in
the last five years, select 'None.'
Help: Social Media
Enter information associated with your online presence, including the types of online
providers/platforms, applications and websites that you use to collaborate, share information, and
interact with others. List the username, handle, screen-name, or other identifiers associated with
your social media profile. (You do not need to list accounts designed for use by multiple users
within a business or other organization.)
The options listed on the form are:
ASK
DOUBAN
FACEBOOK
FLICKR
GOOGLE
INSTAGRAM
LINKEDIN
MYSPACE
PINTEREST
QZONE
REDDIT
SINA
TENCENT
TUMBLR
TWITTER
TWOO
VINE
VKONTAKTE
YOUKU
YOUTUBE
NONE
The next question on the form is also:
Do you wish to provide information about your presence on any other websites or applications you
have used within the last five years to create or share content (photos, videos, status updates,
etc.)?