Intel already stated in its roadmaps that it plans to have G35 a new graphic version of Broadwater chipset known as Broadwater refresh in Q3. Once a company states something like that it usually means that it will ship in very late Q3.
G35 will go to the first customers in middle of September, just two weeks before the end of the quarter. This will only affect the customers that placed the order in middle to late July.
If you are motherboard manufacturer and you will place the order in this period you will still have a chance to get you golden sample motherboard in late September and probably ship a motherboard or two in last days of quarter.
Realistically G35 integrated motherboards will come in serious quantities only in October time and it will definitely make the financial difference in Q4 2007.