Nobody speaks modern standard Arabic as a native language. Each region has a distinct dialect, a modern language descended from Arabic, as Spanish is derived from Latin. But the modern standard is still almost always the choice for formal occasions like political speeches. This was the language in which Hosni Mubarak delivered his speech last Friday.
He avoided Zine el-Abidine ben Ali of Tunisia’s decision to give his speech in dialectal Arabic. That was the first time Zine ben-Ali had done so. He was clearly reaching for Tunisian nationalist emotions in speaking as the people do in their homes and on the streets. It failed.
Hosni Mubarak, by contrast, chose modern standard Arabic. His predecessor Gamal Abdel Nasser was known for using Egyptian colloquial in speeches. But Mubarak did not follow this practice.
He must have felt that Ben Ali’s decision made him look desperate.
Source: Reddit Blogs