With the launch this week of Ping, as well as the excitement around Facebook Places and Google Priority inbox, the news from Twitter that registered users of the site have reached 145 million has gone slightly under the radar.

This is an increase from 105 million registered users only four months ago, which means that Twitter is adding around 300,000 new users every single day.

Mobile playing its part

As discussed this week in relation to Facebook Places, the growth of mobile is playing a big part here, with 16% of new Twitter users signing up via a mobile device.

With Twitter for iPad finally arriving this week, this growth is only set to continue.

So, while there might be new kids on the block, let’s not forget the (relatively) old guys yet…

photo credit: respres