Yeah those 42k are a good start I think, although this game should actually be able to sell more first day. But with the trash it gets, the stupid release date and the relatively poor advertising this is at least not bad.
I hope now that it is able to sell in the 50k-100k range in its second week and get some legs after that. I think gold should be the goal in NA and with a little luck the game will catch fire in europe (were the release date is much better) and maybe become platinum after all is said and done.