The answer will vary depending on the person you ask. Earlier today, I read a comment on a photo (of a cookie cutter kickflip, of course, over a stair set) that read "This is skateboarding people!" At that point I had to stop and ask myself "Is it? Is this skateboarding?," to which I replied to myself, "yes, it is." And in the opinion of the person making the comment, and based on their personal experience combined with their lack of any knowledge of skateboarding history prior to 1999, yes it "is skateboarding people!" But the definition is open to various interpretations. Keep an open mind.
Today it seems as though too much emphasis is placed on certain tricks and attitudes. Individual style and having fun are really the important things (to me) in skateboarding. It's why I started skating to begin with. It was never about being part of a team or being a follower. Skateboarding, as Ben Schroeder said "is about you and your skateboard." That's it.
I think photo credit is due to SoCal SKATESHOP, but I don't know.