In your slider bar for how much time you have, I would recommend having some dynamic text above the dot displaying how much time I have selected. It's a bit confusing trying to discern the exact number between the discreet quantities (e.g. between 5 and 10 minutes, is it 7 minutes or 8 minutes).
Also, Instapaper nailed it with the "Saving ..." > "Saved!" language in the book mark. If you are using the name, go the whole hog and copy that - the feedback to the user that it is safely stashed on the Insta~ servers is invaluable.
(Be even better if it could work with embedded Youtube/Vimeo on other domains, like devour.com).
It will work with embedded videos very soon. We're tracking down some errors in a JS DOM parsing library that the web app uses.