Raw was Vince McMahon's masterpiece. A lot of people might think Wrestlemania is, since it is the biggest wrestling event in the world each year. BUT Raw was revolutionary. Even from the beginning, they did everything live for a while. I think the Manhattan Center gave the show a very comfortable feeling.
But mostly, it became a show that wrestling had never seen. Most shows on the TV never had matches between good wrestlers. It would be a local jobber like Iron Mike Sharpe, Barry Horowitz or the like. But Raw mostly had matches without jobbers. It progressed the story lines, which wasn''t done well on the regular shows. There were title matches, surprises, and things like that.
And of course Raw was the show that set up the Monday Night War, giving WCW the idea to do exactly what WWF was doing.
But yeah, even though it has been AWFUL lately and I freaking hate the fact that it is 3 hours long, it is the most successful AND influential wrestling show ever.