I want to post this in off-topic rather than in the 2012 forums because I don't really know how they are relating it to 2012, if they are at all.
It seems like everytime I do a search for gravity and try to figure out its purpose, cause, and how it works…in the forums section there is always someone explaining away their electric universe theory. Or Plasma cosmology, or saying that the universe if fluid, that magnetics are the key to our universe, yadayadayada
I am not a physicist, I am not an astronomer, so what I read I don't know how to distinguish fact from fiction in these fields.
Here is a post explaining gravity that comes up maybe second or third in googling "gravity"
http://www.wisegeek.com/what-is-gravity.htm
If you go towards the bottom of the comments, maybe like 20ish, you will start seeing people getting into electric universe after some people display their frustration in not being able to find out how gravity works.
I know Phil Plait thinks the idea is dumb, but its strange to see so few comments about it from scholars.