The CAMES program is an excellent way to rapidly improve your Arabic, and overall, an experience I would strongly recommend. Three elements of the program are most significant:
Firstly, the quality of teaching exceptional. Not only is Program Director (Dr. Mahmoud Al-Batal) a world authority on teaching Arabic as a second language, but each of the teachers and tutors has extensive experience in teaching the language and are consistently supportive. Shout-out to Yomna, Safaa, and Khodr. I came into the program with an intermediate level of spoken Lebanese Arabic and no FusHa, and in two months my level of both Lebanese Arabic and FusHa had increased significantly.
Secondly, the cultural program. I had visited Lebanon numerous times before undertaking this course, and nonetheless I was constantly learning new things about the country and its history. There is a weekly lecture in Arabic on a political, historical, or cultural topic, as well as a weekly film screening. These events are a fantastic opportunity for students to substantially expand their vocabulary and their cultural knowledge of not just Lebanon but also the Arab world more generally. It's one thing reading a textbook about US Foreign Policy in the Middle East, and another thing entirely to immerse yourself in Arab culture and history as Arabs understand it, and for that reason I found this aspect of the program extremely rewarding. In addition, most weeks there is a group excursion, which allows you to see the most important touristic and cultural sites in Lebanon, in a comfortable and safe fashion. On these trips you travel all together in a big bus, stopping for food and big lunches etc. Yes, these days are touristy, but they are a stress-free way to see Lebanon. If that isn't your style - no problem - you can organise a separate trip for yourself either alone or in a small group, which many students did.
Finally, the AUB is a wonderful university with all the facilities you could want, including a new gym, running track, pool, and the Jafet library which is a perfect spot to study after class. There's also a cafeteria on campus serving lunch for approximately 10,000L.L. ($8 US), and countless restaurants and cafes in the surrounding area of Ras Beirut/Hamra. Overall, the campus experience is fantastic if a little intense (such is the nature of Beirut!). In terms of safety, the campus is a closed one with guards at all entrances and patrols 24/7 so you'll feel (and be) very safe. Dorms are separated male/female, and escorts are available from the gates to dorms at night so there's never a need to walk to your dorm alone.
A few recommendations:
First, be aware that the course is very intensive. In my experience, most students didn't notice how hard the course was until about the fourth week, so keep this in mind, and pace yourself. That said, the communal nature of the course and the cultural / leisure elements mean that despite its intensity the course is still a whole lot of fun.
Second, the more your practice before your Arabic arriving in Lebanon, the more you will get out of the program! (Not obligatory, however. You can turn up with any level, as long as you're ready for the workload).
Third, make the most of your time in Lebanon - go on the trips, discover the area surrounding the university, and if possible, try and travel around in your spare time. The University can give you recommended taxi companies, and sometimes these companies will drive you around Lebanon for a whole Sunday at a reasonable cost. Don't wait until late in the program to discover Lebanon.