Apart from being a reference to the music by Junior Walker & The All Stars, what is the meaning of the episode's title expression "Shake and Fingerpop"?
It is rather cryptic, but might refer to Maryanne at the end, who is shaking while her hand transforms. Apart from that, the lyrics of the song talk about "dancing like we never did before" (that line also summarizes the main gist of the song), which might allude to the escalations at Tara's birthday party.