Sorry, you're all wrong and it is proved by many reputable on line test sites and also anecdotal evidence by posters who have had and used both, like I have, the D800 has better high ISO ability than the D700. Here is one such comparison from DXO Mark:
http://www.dxomark.com/index.php/Cam...rand2%29/Nikon
As for there being 36Mp on a small sensor and therefore will show noise more than a less Mp'ed sensored camera has been shown to be completely false and and old myth. The crop of new high Mp'ed sensored cameras show lower noise at all ISO's than most of their lower Mp'ed counterparts of the past.
Having used both of these cameras
extensively, 14,000 actuations on the D700 and 14,000 on my now sold D800 and a further 5,000+ from my D800E and I can assure you that the noise from the D800/E is better at all ISO's than the D700.