Nikon is rumored to release a new D4 firmware update. The new version could be out as early as tomorrow. I have no details on what will be included, but I doubt we will see some of the D4s upgrades to trickle down to the D4.
The Nikon D4 memory card issue (when using the cameras with any of the SanDisk Extreme Pro CF 160MB/s and Sony XQD S cards at the same time) has been fixed by SanDisk and do not require a firmware update.
If you have a defective CF memory card, you should contact SanDisk directly and they will most likely send you a replacement. All new CF SandDisk cards should not no longer have the problem. If you are buying, make sure the retailer gives you new stock – there is no other way to differentiate the good from the bad cards.