Let's just say he was not amused. He sent out these two messages viaTwitter:
Seriously Facebook? http://pic.twitter.com/0ifNsdY
Ok Facebook, enough with the flattery. http://pic.twitter.com/vSyHdpH
You can see the first comparison screenshot at the top of this article and the second one below (in both cases, Twitter is on the left and Facebook is on the right):
Haggerty is implying that Facebook has copied Twitter's iOS app user interface. The saying goes "imitation is the sincerest form of flattery" but clearly Haggerty is not flattered.
In Facebook's defense, both designs reflect a respect for the iOS standard constructs, including placement, sizing, and coloring of the icons. Nevertheless, the screenshots do show a remarkable similarity. What do you think?