Spotify are constantly improving listener experience, this time focussing on their premium users. You want to be in control playing music from the start, so they've introduced a new shuffle button to allow you to play music on shuffle right away. As mentioned by Spotify:
Music—and how you listen to it—should be yours to control. So from the moment you hit play on Spotify, you decide the way you want to hear your favorite playlists or that new album you’re obsessed with.
This new change will allow you to choose the mode you prefer at the top of playlists and albums and listen the way you want to. Whether you love the joy of the unexpected with Shuffle mode, or prefer listening to tunes in order by simply pressing Play, Spotify has you covered.
They're rolling out this update on iOS and Android mobile devices for Spotify Premium users worldwide over the coming weeks, so stay tuned for more.