This 72 virgins story has been abused and used as a propaganda tool by Muslims and non-Muslims alike. As with most things, the answer is in the interpretation.
Firstly with respect to suicide and therefore suicide bombers, is forbidden in the Traditions (Hadith in Arabic), which are the collected sayings and doings attributed to the Prophet and traced back to him through a series of trustworthy witnesses.
However a distinction needs to be between the martyr and the suicide bomber. A martyr killed in a real Jihad is an honourable thing to do in Islam, and rewards in paradise for this are offered. What occurred on 911 was not a Jihad, but mass murder. In Iraq Ayatollah Ali Sistani – the leader of the majority of Shia’s has not declared a Jihad, similarly in Afghanistan and its religious authorities.
The Quran does make reference to virgins, though the definition of the word virgin is disputed. Some claim the definition of the Arabic word “Abkarun” is not virgins, but Angels.
Christopher Luxenberg’s book, Die Syro-Aramaische Lesart des Koran, available only in German, has an enjoyed an enthusiastic reception, particularly among those scholars with a knowledge of several Semitic languages at Princeton, Yale, Berlin, Potsdam, Erlangen, Aix-en-Provence, and the Oriental Institute in Beirut.
Luxenberg tries to show that many obscurities of the Quran disappear if we read certain words as being Syriac and not Arabic. Luxenberg claims that the context makes it clear that it is food and drink that is being offered, and not unsullied maidens or houris (virgins).
In Syriac, the word hur is a feminine plural adjective meaning white, with the word “raisin” understood implicitly.
In conclusion – No, Muslims, who are fully-aware, do not believe that should they die as martyred that they would be rewarded with 72 virgin maidens.