With the latest release of Dropbox, you can now plug in your iPad, iPhone, memory card, etc. into your computer and upload your photos or videos to your DropBox account. The process takes place automatically.
In order to encourage you to use the service, Dropbox will give you an additional 500 MB for your first automatic upload. As you take and upload more photos and videos, you can earn up to 3GB extra for free.
Dropbox explains the latest photo upgrade on their blog site.