Crazy!!  
Is Nikon off their collective rocker?
Today Nikon introduced the D700 replacement.  
Is the mega pixel war on again.  I thought we would see an increase in quality pixel instead of a numeric increase.  Is this kin to shoehorning a 454 ci V8 into a Vega? Is this a combination that is only great in a straight line?  
The D800 does have some other great numbers "91,000-pixel 3D Color Matrix Metering III and the Advanced Scene Recognition System, coupled with an improved 51-point AF system"**.  Add to this 1080p video at 30/24p with HDMI output and the feature add up to a fine offering. Native ISO is better, "the D800 features a wide native ISO range of 100-6400"**. 
The mega megapixel does make its mark in the continuous frame rate.  The rate is down to 6 frames per second in DX mode and 4 frames per second in full resolution FX mode.  This is rolling back to the days of the D70s (a great little camera) and far from the 7 frames per second of the D300s without the battery pack.
Not all is bad here.  Many photographers (Wedding, Fashion, Landscape, Commercial, etc.) will find good use of those 36.3 Megapixels. It want be a fit for every photographer and the QUALITY of those pixels will need to prove out the features for the D800 to become the right fit for the curves in your photography.
The fit for the D800 is the controlled subject photography where we craft the image to fit with our client’s needs.  The samples Nikon is making available demonstrate really good clarity and sharpness.  The import thing here is the samples show more of the type of images that Nikon believe the market will produce.  The market for the D800 is the photography of the clients wedding, the car for the trade magazine and the product advertising shots.  Landscape, Architecture and some wildlife photographer will find their stride with this new offering. 
The talk has started on the optional “D800E” variant. Will this be the go to camera? The offer of increased sharpness  in your project be practicalIncorporating an “optical low pass filter (OLPF) without anti-aliasing”** has benefits yes.  But the margin for introducing unwanted digital monster increases. In general the patterns where these monster lurk are can be controlled. For me and many I do not know if the risks will out weight the reward.  The ROI on the “D800E” will need some proving so its benefit is understood.
The D800 Video quality is amazing. That said I do not have the experience to judge it performance.  Go to the video samples at NikonUSA and judge for yourself.
The more you look into the D800, the more you find that will excite you.  Yes I believe Nikon got off the rocker and produced and exciting camera.  I am looking forward to seeing the D800 handle the curves.
** Information cited from Nikon USA.