In a sharp programming shift, Day 1 went from the psychedelic pop of Olivia Tremor Control into the mixtape hip-hop of A$AP Rocky. The only similarity I can think of between the two acts is that there are higher than average odds that both their listeners partake of illicit substances.
Walking into the photo pit at the start of Rocky's set, the presence of pot smoke went from occassional to all-encompasing. Photographers were even smoking joints while jockeying for position in front of the stage- the only time I've ever seen that.
The crowd quickly doubled in size, but quadrupled in excitement. Women in elaborate bathing suits suddenly appeared among the fans. Kids in front knew every word of every song. All this for a rapper who still hasn't released a proper album (but did recently sign a $3 million deal with RCA).
As an outside observer to the hip-hop mixtape world, this set reminded me of Odd Future's performance at Pitchfork 2011.