Having helped spread dissent across the Middle East, Twitter now has the backing of one of the region’s richest men. Saudi Arabia’s Prince Alwaleed bin Talal and his investment firm have invested $300 million in the microblogging website. That amounts to a 3.75 percent stake, using the $8 billion valuation frequently cited by analysts. Alwaleed is said to be worth $20 billion and also owns large stakes in News Corp. and CitiGroup.
