Can I have some advice with MIL cameras?

I'm a novice who is looking to step up in the world of photography and cameras. I was looking at DSLRs and was looking into getting a Nikon D3100, then I discovered the mirrorless interchangeable-lens cameras. I went into my local camera shop for some advice and they recommended I look into the Panasonic Lumix G series. I then asked a friend and they recommended Sony NEX-3 or 5. What would you recommend? Panasonic? Sony? Other? Or would you go for the Nikon D3100? I have a max budget of about £500, and want a camera which will take great images but also will help me learn the ropes. Any advice would be welcome. Sorry for going on a bit.

Had a nex3 which i did not like image quality wise, i don't think the sony lenses are all that great
now using samsung nx100 and getting far better results, you can pick one up for around £200
on ebay

The problem with these cameras is that they are a compromise, they are still in their infancy, and if you buy now you'll be what in marketing terms is called an "early adopter" few products in this phase of development has really had all it's teething problems dealt with, so you do get a feel that the product probably has more to give. For example, the NEX is a very capable camera, but is badly let down by lens selection. The Lumix G (on the MicroFourThirds system) is considerably better on lens selection, but it's let down by it's small sensor.

In time, the MILC will develop, but right now, in 2011/2012 I can't make the recommendation to buy one. Stick with the DSLR until the technology has matured.

I would stick with the d3100 slr because it is a much better camera to learn with.
These type of cameras you describe are relatively new. If anything it's people who have dslrs already who may tend to buy one of these as well, maybe as a lighter, travel camera.