Rocksmith on Steam was the lack of Maroon 5 songs, we'll just remove that musical obstacle for you right here and now. Valve reports that "Misery," "She Will Be Loved," and "Harder to Breathe" have all been added to the game.
You can buy each song for $2.99, or pick them all up together for $7.99. Once purchased, you can play through the songs with a standard electric or bass guitar, and each song also adds a new authentic tone to play with on the game's Amp mode. Sweet Maroon 5-style haircuts are, unfortunately, sold separately.