Here is a recent piece of news about the speed of gravitation; PhysicsWeb seems a reputable source to me:
http://www.physicsweb.org/article/news/7/1/2. According to this, the speed of gravitation is equal to the speed of light (within experimental error).
>Hi Hilmar,
> Due to some of the latest research being done large cracks are starting to appear in the currently held beliefs, i.e. Gravity's effect travells at greater than the speed of light, possibly by a factor of 20 fold. Check this link out
ftp://rock.helsinki.fi/pub/misc/matpitka/padtgd/Zanom.pdf
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)