Thanks for your input Navajo. I think the Islamic countries in the Middle East are playing and will play an important role in end times prophecy. For example, you can find references to Edom, Egypt, and Libya in several prophecies. But what I don't see is a clear reference to Islam as a religion or as some type of unified kingdom.
And in regard to Islam being the fourth kingdom of Iron in the prophecy of Daniel 2, I think that interpretation has several problems. First, if the image from the vision shows the Babylonian, Persian, and Greek kingdoms just prior to the iron kingdom of the legs, where is the Roman Empire? Is it so insignificant that it can be completely ignored?
And second, your linked article claims that Islam conquered all of the previous kingdoms and since Rome never conquered all of the territory occupied by either the Persian or Greek empires, it can't be the iron kingdom. But neither did Islam conquer all of the territory that Rome controlled. Although Islam made significant progress in the Iberian Peninsula they never controlled most of continental Europe or England. And the Roman Empire directly succeeds the Greek Empire of Alexander. By the time Mohammad was born the empire that Alexander ruled was something that only the historians would know about. So how can Islam be said to crush and break the previous Greek kingdom?
Also, it is important to remember that Bible prophecy is generally given relative to the land of Israel. When it talks about something from the north or the south, it means north or south of Israel. The same kind of thing applies to the kingdoms that are mentioned - they are the kingdoms that controlled the land of Israel at that time and have little to do with the extent of their control in distant lands.