Despite previous announcement, Google and Samsung have announced that they have decided to postpone the announcement of both the Nexus Prime and Ice Cream Sandwich. In a joint statement by the two companies, both Google and Samsung feel this is not the right time to announce a new product.
Samsung and Google decide to postpone the new product announcement at CTIA Fall. We agree that it is just not the right time to announce a new product. New date and venue will be shortly announced.
Source: Google and Samsung Official Statement