Originally Posted by Aric

Page titles can be set in the "Page Copy" area under SEO & Analytics. Your index page will use your tube "slogan" (in Site Details) if not set in the Page Copy options.

Block titles on the index can be edited in the "Content Blocks" area under Design & Layout

Video titles -- preview your tube from the editor. Click on a video to get to the player page. Double click the video's title text to change to edit mode. Type your text, hit enter when done. We'll be adding more efficient tools to do custom video titles/descriptions in the near future.