FUD Zilla heard NVIDIA plans to release a new dual-GPU card in December:
The new card is based on two GF100-derived cores, probably similar to the GF104, so we can only imagine the TDP of that card. Our educated guess for this time is at least 400W card, something that will get very hot indeed. It would appear that we are almost at the verge of a new era, where water cooling will be a must.
AMD also plans Antilles, Radeon HD 6970 dual Cayman card, and this one also looks to be quite a hot one. A GF100GX2 was on the roadmap for quite some time, but Nvidia never decided to release the card. We guess that chose to drop it because of its enormous TDP, courtesy of two GF100 chips.