About the language
One common myth is that Arabic is an extremely difficult language. In truth, Arabic does not belong to the Indo-European language family and is built on entirely different rules from European languages. Arabic grammar is quite clear, and its logical word formation often lets you guess the meaning of an unfamiliar word. As for pronunciation, it is a matter of practice and poses no intellectual barrier for learners.
Another misconception concerns the very nature of Arabic. Modern Arabic is divided into two varieties: the formal literary language, used throughout the Arab world, and the spoken dialect, which people in a particular region use in everyday life. Formal Arabic is used in the press, on radio and television, at conferences and so on. Spoken Arabic is what you will hear at work, at home, in songs, in films and in soap operas.
Universities around the world teach classical, standard Arabic, in the belief that it is the "pure" form and that it allows you to communicate in all Arab countries, while local dialects are seen as something like regional slang. None of this is true, because in practice this kind of "communication with the whole world" turns out to be very limited. If you know only classical Arabic, you simply will not be able to speak properly and fully with people in their native language. Communication will be one-sided, and misunderstandings will often persist until a native speaker of the local Arabic reads what you meant to say. Naturally, you will not be writing everything down every time. There is only one solution: know both the standard and the spoken language, and use one or the other (or a mix of both) depending on the situation.