Right, think I've got it.....
They've all had their biggest hit to date with a chart entry on downloads only (probably not very well worded)...
Sandi Thom entered at 15 with Punk Rocker... on downloads only, her biggest hit to date at that point
Nerina Pallot entered at 34 on downloads only, her biggest hit to date at that point
Automatic entered at 23 with Monster on downloads only
Sergio Mendes entered at 29 with Mas Que Nada
Egg at 28 with Love Don't Let Me Go (Walking Away)
Scissor Sisters at 4 with Don't Feel Like Dancin'
Killers will join them on Sunday if they enter higher than 3 on downloads only with When You Were Young, beating Somebody Told Me which got to 3.
Either this is right, or I will look a right spanner......