Lowercase "internet" refers to any network of networks, for example a router which lets machines connected via Ethernet talk to machines connected via WiFi.
Capitalised "Internet" is a proper noun referring to a particular network of networks which began life as the ARPANET.
"Wiki" refers to user-generated Web sites in the style of WikiWikiWeb; since you put it in a list of Web sites/companies, I'll presume you meant "Wikipedia", which is a particular Wiki.
So whilst AOL, Google, Yahoo, Facebook and Wikipedia aren't "The Internet", at least your hypothetical "Majority" have enough respect for the Internet to refer to it by name.