I'll throw in a plug for micro4/3. I switched from Nikon DSLR to Olympus OM-D cameras and m43 lenses and have been absolutely thrilled by my choice. It's an excellent system, especially for travel.

I have a Nikon1 V1 as well. My issue with that system is that the lens quality isn't as good as m43 and there aren't as many choices either.