Re: MUX Raking
Yes, the 'temporary' additional muxes don't have full coverage. I think it's something like 75% off the top of my head. They're part of the lure (and what could be more alluring, surely, than QVC Beauty in HD?) to persuade more people to get receivers that support T2.
Another of the lures is on COM7: Al-Jazeera Arabic. You may not be bothered about watching it yourself, but as I wrote when it launched, it represents a significant step in the evolution of Freeview, as the first SD channel on a T2 mux.