Woodstock’s into

[Peanuts, November 25, 1978. Click for a larger view.]

Yesterday’s Peanuts is today’s Peanuts. Yesterday’s colloquialism is today’s colloquialism.

The first citation in the Oxford English Dictionary for this use of into — “interested or involved in; knowledgeable about” — is from Rolling Stone, January 28, 1969: “I tend to like the stuff the rock groups are doing because they're creative and original, and that's something I'm very much into.”