This is one of the more-interesting datapoints I've seen regarding the current situation in the Middle East:
As the original source notes census data suggests about 7.4 million, but 50% of Gazans think the correct number is a million or fewer. Here's an interesting quote from the piece on how it impacts the prospects for peace in the region:
Lacking basic knowledge of Israeli society is also correlated with support for attacks on its civilians; in TWI polling conducted in the West Bank, there is a twenty two percentage point increase in those who say that attacking ‘all Israeli Jews’ is a bad thing among those West Bank residents who have a more realistic perception of Israeli Jewish demographics.