If you've read any of my review posts before I'm going to sound like a broken record, but...
If you're handling anything which could be considered personal data, you need a privacy policy, a TOS page, and a way to export that data. From looking at your site and watching your video, I can't tell whether you intend to sell my list of clips to advertisers, connect it to my name and make it available in a data dump, or any one of 100 other things I have no interest in you doing.
As for your web page, why make such a user-unfriendly thing as a log-in screen your main page? Why not include the video on the main page so I don't have to click 3 or 4 times to start finding out what the heck your service even is.
That said, I think you get it, and that's refreshing. For me, Google Notebook and Evernote are too linear. Zoho Notebook is too complicated. No one else has really sparked my interest.
The two main features I want in an online notebook are the ability to grab anything from anywhere with minimal effort and the ability to organize things freely. These you deliver quite well.
There are a few features I would definitely consider.
1. Inline notes. If a note is really short, it would nice to be able to just stick it on the page as plain text, instead of having to double click to open it. This would add a lot to the ability to freely organize things because you could use notes as headers, separators, whatever.
2. Inline pictures. Since there's a little preview of the picture anyway, why not let me clear away the title and URL and just show the picture. Then, if you're doing that, why not let me resize it. Again, this goes to letting me freely drag stuff around however I want it. It would also let me use a picture as a background or header or just about anything else.
3. Sharing at least read access to a project with someone else. This is pretty big. The reason I started looking into online notebooks in the first place was to plan vacations with my fiancee. I can share login details, and that's fine, but eventually, I'm going to want to share a view of a project with someone I don't trust with my login.
And one little minor thing. Double-clicking an open folder should close it.
I also think it might be cool if you could arrange things inside folders just like you can on the main project page. At the very least, reordering would be nice.
Just so we're clear after all that: My overall impression is very, very positive.