A blog hop is a linky list that is SHARED ON MULTIPLE BLOGS. When several blogs put the same linky list code on their blog, the exact same list appears on each blog.
Blog visitors can submit their entries on any blog that contains the list. The entries will appear on each blog where the list resides.
Blog readers see the same list on each blog, and can "HOP" from blog to blog seeing the same list of links to follow: BLOG HOP!