All of this user interaction should make Twitter stickier, keeping users on the site longer.

And that would help Twitter continue its momentum.

Earlier this month, showed that Twitter may not be gaining new U.S. users as fast as it used to, but the users it has are much more engaged.

This past February, about 15% of U.S. adult Internet users use Twitter, the report noted. That number is slightly up from the 13% who said they used Twitter in May 2011. And that figure was up from 8% who used Twitter in November 2010.

However, the report also showed that while new user growth is slowing for Twitter, the percentage of engaged users is climbing.