Most ideas are "coming soon", that means the site is quite "useless" (not to be mean, just pragmatic) right now. Also to be really attractive you would need a lot more ideas, and more varied ones.
Submitting ideas via social media is not a great idea IMHO, mainly because people might not use those social medias, a way to submit ideas from the site would be more appropriate.
It is actually quite unclear that we can submit ideas, the user has to go to the "about" page, which is tedious. If I were you, I'd indicate that possibility on the front page.
I see there is a way to register and login: what for? Since the site is quite simple (you come for a project idea, which you get as soon as the front page) I don't see the point, so if there is any advantages to register, you should indicate it on the site, if you have features you should "advertise" for it.
It's more debatable but: you should go open source (if it is already, it's not clearly said, so I assume it's not), mainly because among the many advantages of open source, that would be a nice way to crowd-source your project ideas.
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No problem :)
Another few things I can say about the site: