I made this post and he responded with this.
I checked out this section and it looks like the people who are running signature campaigns are legendary or have some of the green trust.
You have neither? Shouldn't you be using a middleman so no one gets scammed?
If you feel uncomfortable about participating now, you can wait a few cycles. We intend to carry on this campaign for a while.

I think he's going to scam for the first 2 weeks and then just run off with free advertising. With this post he is basically avoiding to use middleman and having 0.5 BTC doesn't necessarily mean you will pay out the 0.5 BTC. I hope I am wrong here...
Also getting paid 40 cents a post seems hella nice.