When I joined Steemit nearly 6 months ago, I had no clue about the differences between Steem, Steemit, Steem Dollars and Steempower.
I thought that Steem and Steemit were kind of the same thing. And putting busy.org into the mix - made it even more complicated (and this was before the time of utopian & dtube).
Now, after developing the last 5 months with Steem and becoming a Witness - my knowledge about the Steem-Ecosystem became quite good (and is still getting improved day by day).
However, I see many users who have the same problem I had many months ago.
Luckily, there are already a lot of good posts; for example this: Steem, Steempower & Steem Dollar Explained which explains the different Currencies; or this post What is Steem?- which explains the Ecosystem - and that's why I won't get into detail about that.
(The following text will however require a basic understanding about Steem - so I advise to read the linked posts above, if you don't know what the difference between Steem and Steemit is)
Nevertheless, my feeling is that many people overvalue Steemit and undervalue Steem.
Steem is more valuable than Steemit (and all other Frontends)
I got interviewed recently by 
About how I would change Steemit - and why I became a Witness for Steemit.
Now, as you probably know - Steemit is not a blockchain - it is one of the interfaces of Steem. So the question is wrong (but I still gave the correct answer).
I believe that the reason, Steemit is getting valued so high, is because many people created a Steem Account through Steemit - so they believe that Steemit is the main-part in this whole Ecosystem. Similar to Facebook.
But the truth is, while Steemit is currently very big, in the future it will only be one part in the whole Steem-Ecosystem.
You just have to look at how popular other interfaces like utopian or dtube are becoming.
In essence, Steemit is simply a website on the internet - but in this case, the internet is Steem, the blockchain.
My goal as a Witness is to support and improve Steem - not Steemit
In the interview I also said the following:
Q: how are you going to support steemit as a witness?
A: There is a big difference between Steem and Steemit. Steem is the Blockchain - while Steemit is simply one approach to use the Steem-Blockchain as a SocialMedia-Site / Blog-Plattform. Another interface is for example utopian or dtube.
I personally will work on improving Steem as an Ecosystem for Apps & Businesses - and not really on making Steemit greater.
While Steemit is important, I think there are Witnesses who are better suited for this task.
The first part is pretty much the same thing I said above, but what I want to highlight is this sentence:
I personally will work on improving Steem as an Ecosystem for Apps & Businesses - and not really on making Steemit greater.
As you might know - I've created a plattform called smartsteem.com - which offers different services for vote-buying & vote-selling. And some people don't think that those services help Steemit grow.
And they are right - the most important thing for Steemit are communities. And smartsteem is currently not helping there.
However, my goal is not to support Steemit, but to support Steem - and the blockchain actually doesn't really care where the votes came from. If they were bought or not.
Steem needs Investors & Developers
So, what helps Steem grow is the amount of activity and development it receives and most importantly: new investors who are attracted to invest into Steem.
And that's where e.g. Vote-Selling has its shining moment.
Giving Investors the ability to buy Steem as investment, powering it up - which then increases the value of Steem (incl. Post-Payouts) by reducing the amount of liquid Steem - and then using this Steempower to generate passive income through Vote-Selling (with an easy to use interface) is helping Steem grow.
