I thought Jay really nailed it on his lift explanation. He explained things in a very accessible way, but still described the depth and nuance of the core concepts. I studied fluid dynamics while getting my applied math PhD, and I always struggled to explain lift to non-technical audiences.

Jay did a great job of describing a key problem with explanations of lift-- people often want an "A causes B causes C...." approach. Instead, the situation with faster, low pressure flow above the wing and slower, high pressure flow below the wing represents a dynamic equilibrium.

A couple of analogies are useful.

Consider the flow of waters in a river with protruding rocks. The obstacles generate a pattern of flow (the "streamlines"; paths that a rubber ducks would follow if dropped in the river). Different locations in the river have different flow directions/velocities and different pressures, depending on the geometry of the obstacles. Some people would say that the pressure differences cause the flow direction/velocity. Others would say that the flow direction/velocity causes the pressure differences. A more useful idea is that the geometry of the obstacles sets up an equilibrium flow (which can be found from the Navier-Stokes equations); at each point in the river there is a relationship between flow direction/velocity and pressure.

Alternatively, consider the distribution of matter in a galaxy. You could say that the gravitational field determines the distribution of mass, or that the distribution of mass determines the gravitational field. The key idea is that the distribution of mass and the gravitational field are related to each other by a simple equation. In the airfoil or river examples, the equations are the Navier-Stokes equations.

Finally, Jay mentioned planes flying upside down. An airfoil with a longer tip-to-tail distance on the top of the wing than the bottom of the wing is not necessary to generate lift. Instead, it is the total geometry of the wing in relation to the fluid flow that generates lift. The geometrical configuration is due to both the shape of the wing and the angle of attack. You can generate lift with a wing that has equal top and bottom lengths, or even with a wing that has a longer bottom length (as in the case with an upside-down normal wing), provided that you change the angle of attack enough. In a river, the relative flow to the left and right of a rock are determined both the the rocks shape, and by how the rock is oriented in the river.

A useful picture is in the third diagram on this site:

http://hyperphysics.phy-astr.gsu.edu/hbase/Fluids/airfoil.html