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Albert Einstein may have been right that gravity travels at the same speed as light but, contrary to a claim made earlier this year, the theory has not yet been proven. A scientist at Lawrence Berkeley National Laboratory (Berkeley Lab) says the announcement by two scientists, widely reported this past January, about the speed of gravity was wrong.

If the idea of gravity propagating at light speed is a requirement of relativity, then it's time relativity was dropped. Gravity is known by experiment to propagate either instantaneously or close enough thereto that our best instruments cannot tell the difference.

Tom Van Flandern's page on the topic at Metaresearch notes that:

By contrast, gravitational forces are large, readily detected, and control the dynamics of most of the visible universe. Gravimeters easily detect the gravitational force from, and motion of, a person entering a room, for example. The propagation speed of gravitational force is bounded by six experiments to be much faster than the speed of light.
[[5]]. For example:

In 1825, Laplace determined that the minimum speed of gravity consistent with observations was at least 10 million times the speed of light, c.
Modern, high-precision solar system observations show that the direction from which the Sun's light comes, and the direction toward which the Sun's gravity pulls us, are not the same. The former is retarded by the time it takes light to travel from Sun to Earth, 8.3 minutes; and the latter is not retarded by any detectible amount.
Eclipses of the Sun by the Moon occur about 40 seconds before the time of the Sun's maximum gravitational pull on the Moon. The delay indicates that light and gravity do not have the same propagation speed.
A 1997 laboratory experiment by Walker & Dual showed that gravitational signals propagated much faster than light signals.
Binary pulsars (with large masses and speeds) show that the speed of gravity must be at least 20 billion times the speed of light.

Van Flandern stops just short of calling Kopeikin an outright fraud.

Sorry I'm late to the party. Work does that to me...

Anyway, it seems there's some kind of brew-ha-ha about GR and the position of the Sun. A few points to keep in mind:

1. The Sun and the Earth are both moving, roughly in tandem, around the Galactic center, towards Andromeda, towards the Great Attractor, etc.

2. From the Earth's point of view, the Sun is always where it "really" was 8 minutes ago.

3. If gravity moves faster than the speed of light, we have a problem with causality. By definition spacetime moves at speed c. If gravity moved faster, then objects would affect each other without "seeing" each other. That makes no sense.

As for General Relativity, ever measurement from Mercury to stellar occultations to binary neutron stars to rocketed atomic clocks confirms GR exactly.

MD, whose PhD dissertation was about gravitational lensing