48khz is DVD standard but I've never heard of using specific multiples of rates depending on destination? Maybe someone could explain the theory?
You can record at 44.1khz and benefit from smaller files and lower system overheads and not have any problems. It really depends on the quality of your equipment.
I think that a lot of professionals record at higher sampling rates to 'future proof' their work against advances in technology.
My Christmas morning pennies worth before the madness starts.