In short term I think that some advertising of the blockchain by different conferences and interviews of Ned being held all around the world will give it a boost as well as the launch of SMTs next year, in March.
On the long run to attract investors Steem has to prove that it has a reliable business model that works almost flawlessly attracting and holding those investors. Steemit, as a blogging platform needs to mature itself a bit and earn its name as a profitable one both for investors and the ones using it.
I, for example, wouldn't invest in a company where the great majority of its employees are frustrated about their income and their working conditions. The same way Steemit has to take care of that trending page, of the rewards pool rapists, of spammers and abuser and of course of its good bloggers.
Bottom line it needs to become more like a company than a wild west with no sheriff in town.