My choices for the top 5 Gmail changes, updates, and features added in 2010 (so far). Mostly these are useful changes for Gmail users, though some are visual changes and re-organization (which result in improved user experience):

  1. Drag and Drop attachments into Gmail
    Darg-n-drop your files from your computer onto Gmail without going through the whole attach a file process
  2. Drag and Drop attachments to your desktop
    Drag-n-drop attachments from Gmail right onto your desktop instead of downloading
  3. Updated Gmail & Contacts
    This was a great overhaul of contacts and a slight change to the Gmail look
  4. Turn off Conversation View
    Not one I’d use, but many users certainly want the ability to turn off conversation threading and view emails all as separate messages just like in “standard” email programs
  5. New Gmail Themes
    5 new themes were added to give users more choices