On Facebook, some members sent e -mail to all the people on address books without noticing. The e-mail is the invitation to Facebook. This might have happened because the contents of the website show ambiguous sentences about sending e-mail to friends on address books.
On the other hand, so far, we don't have to pay attention to misuse Twitter. But, if this function is introduced, some users will confront the same accident unless comprehensible explanation is written on Twitter.
By the way, the headquarter of twitter is in front of Civic Center Station in San Francisco.
When I went to San Francisco in August, I passed in front of the building of the headquarter. But, I failed to take a picture.
