Guys, its up to you, but I have studied Arabic for only 6 months, and already I have reached an intermediate level in writing/reading, speaking and listening with Modern Standard Arabic. Obviously I don't understand easily when people speak heavy in the different dialects - though I find I can understand them about 70% when they mix the two due to context.

However, I know you don't want to read an essay (much less one in Arabic) to figure out which way is up - so I think the other guys are totally right. Study MSA because it is the base language that everyone does understand. They may not always speak in it (especially when talking to someone else) as they may not want YOU to understand. I don't think its reasonable to "guess" which dialect you'll need and hope it applies - stick with MSA and the grammar there.

If you want to practice, feel free to hit me up on skype. Abuheemar is me on skype.

Thanks!