I'm sad that Jedward have been snubbed. They're one of the most iconic X Factor acts of all time, they've done really well since leaving the show and Lipstick is a fantastic song (and did very well at Eurovision).
I realise this wouldn't sell half as many copies, but I'd have loved a more thorough, chronological run-through of all the memorable contestants over the years, with one song per artist. So you could fit in Steve Brookstein, Leon Jackson, Same Difference, G4, Rhydian, Chico, Maria Lawson, Laura White etc. It would have been very nostalgic. Unsurprisingly though, the compilation is focused towards the more recent contestants.