sea level rise is slowing, page-95

I trust this will be respected as a serious attempt to address some comments on this thread.

The average altitude of North America is about 720m.

http://wiki.answers.com/Q/What_is_the_average_elevation_of_North_America

The width of the continent is about 4000km so it's 2000km to the centre.
With basic maths you can see that if you took a circle of 4000km dia and 0.72km height you could reduce that by 1,000,000:1 to give a scale model.
That would give you a disc of 4m dia and just 0.72mm thick.

The average inclination or gradient of that mass is tiny, regardless of how that 0.018% thickness is distributed from the outer edge[sea]to the centre.

Over time this is what counts, not the superficial constantly changing gradients at the edge which result from the action of tides and waves.