MacWorld has a great article on MMS — what you need to know about installing, enabling, and using MMS (multimedia messaging). It explains how to send images, location data, videos, and voice memos. And the article talks a bit about performance. An article on CNet says that some users have had problems sending messages and gives a fix. And while there had been concerns whether AT&T's network could handle the additional volume, AT&T is reported to have said that things have gone fairly smoothly.