Twitter reaches 105 million users

Twitter has more than 105 million registered users, co-founder Biz Stone said Wednesday.

The announcement, at the micro-blogging site's Chirp conference for developers, marked the first time Twitter has announced it number of accounts. The tally - 105,779,710, to be exact - is significantly more than outside analysts had estimated.

The company also says it's adding 300,000 accounts per day, with much of its growth coming outside the United States.