There are even people suggesting that Google+ will replace Facebook.
Not being on FB, I can't compare the two, but G+ certainly also has the tendency to connect you to people you don't want to be contacted by (or don't even know), to the extent that articles are already appearing
explaining how to adjust your settings to keep things more private.
I think as with any social network, the key for users will be in digging deep into the privacy settings to prevent inadvertent revelations to the world when you really meant to just communicate with a close friend or family member. Don't assume default settings protect privacy; on the contrary, they do everything they can to eliminate it.