Eh, personally I don't see a lot of value in cross posting +Guy Kawasaki
. It's okay occasionally, but different outlets should be treated differently. When I do cross post I frame things differently, change things around for a different audience, and make sure that content looks best where I'm sharing (that's rarely a link to a G+ post).
Cross posting, in my opinion, is lazy and doesn't take advantage of the strengths of each network. Personally, I'm turned off when I see people sharing the same content, the same way across several networks. It doesn't incentive people to follow on you in different places. Doesn't mean you shouldn't share the same content in different places, just that you have to be cognoscente of platform, audience, and content framing.