Played this on the Trojan board yesterday or the day before and promised myself to quit before it became addictive, but just had to have another go when I saw it here - with some different artists:
The Who 8/10
Joni Mitchell 8/10
(On the Trojan board I got 10/10 for The Incredible String Band and Bob Dylan, 9/10 for The Wailing Souls and The Wailers, 8/10 for the Ethiopians and 7/10 for the Maytals which was disappointing.)
I've come across a similar game in a pub quiz I used to go to except that in that, they mixed up the artists and genres.