I was planning on getting Soul Silver yesterday but i never got round to getting it.
Might go and get it on tuesday instead.
I didn't know you could catch all the legendaries from all the games. Thats pretty sweet.
The list for Heart Gold Exclusives:
Mankey
Primeape
Growlithe
Arcanine
Spinarak
Ariados
Gligar
Mantine
Phanpy
Donphan
Sableye
Baltoy
Claydol
Kyogre
Mantyke
Gliscor
The list for Soul Silver Exclusives
Vulpix
Ninetales
Meowth
Persian
Ledyba
Ledian
Delibird
Skarmory
Teddiursa
Ursaring
Mawile
Gulpin
Swalot
Groudon
Got that from yahoo.answers :$ Up to you what Pokemon you like more really out of them