On web we saw a 6x increase in the number of Tweet impressions from logged-out visitors browsing profiles and a 2x increase in the number of logged-out visitors who saw an impression of the profiles.
On iOS, the most remarkable change was a 38% increase in people visiting the new profiles and a massive 6x increase in users visiting the media timeline. Similarly, on Android we saw a 128% increase in people visiting profiles and over 2x increase in people visiting and scrolling on the media timeline.
I like Twitter profiles on the iPhone. The profile view (and many other features) could use some love on the iPad, though.