"User-created lists of downloadable videos" may sound simple, but it's deceptive simplicity will make it the twitter and/or instragram of its day, I am entirely certain of it.
How do you plan on getting traction?
What are the legal implications?
How much have you personally invested both in terms of time and money into this project?
What previous projects have you completed?
Can you get a friend to co-found this with you?
Show us something that would indicate you punch above your weight class, eg Academics, Social, Hacking.
Traction is people creating lists. Yes, the ycombinator list got 3000 uniques a day. But ANYBODY can create a very particular list of videos that draws that many uniques or more. More traffic equals more traction.
I have invested a year of work into this project. Self-funding is my development time and hosting costs.
I don't have much in previous projects worth showing off.
Why do I need a co-founder?
Maybe that is part of the problem.
If I were an investor (which I'm not - no experience or skills in that area) I would be interested to hear your answer on that. What would plan "B" be if something like that were to happen?