Competition is fine, but I don't get the "too large" argument. Long before Google came along, there were many indexes and directories that had dominant market shares. For example:
- The Reader's Guide to Periodical Literature (a magazine index used by libraries)
- Books in Print (used by nearly every bookstore in the U.S.)
- Literary Market Place (companies and people in book publishing)
- Hollywood Creative Directory (film and TV production companies)
- The Red Book (advertising)
Google has a smaller market share than any of the indexes and directories that I've just listed.