No, it's not majority Muslim (although it is majority non-white - this might sound like a strange measure to an American, but your "diversity" is interwoven into your history; ours has been imported wholesale over the last 50 years).
The scariest thing isn't the total proportion of Muslims, though, but how many area of the city are 80+% Muslim. Looking at their overall percentage is very misleading, because they are prone to ghettoisation.
Demographics maps (bear in mind this is 5 years old):
http://i.imgur.com/gvcfXlh.png Let's just say there are many areas of that city where white people will not be safe walking at night.