There's nothing wrong with the Fudo core, it was taped out over a year ago and has been tested behind closed doors at E3 I believe. The fabs simply haven't started mass producing the cards yet. You also have to remember that the Fudo looks a lot more complex than the G70, more pipelines, more and newer VRAM, smaller process etc.
Plus there's about a month or so after a card is released that you should wait, drivers will be buggy now and you need to see who gonna deliver software wise.