Do companies actually see the potential of what Google+ is? I am sure not yet and they will not see it for a long time, basically you are able to reach your target market and potential clients without them even knowing you are there, but they will receive your posts about your business so you can reach everyone you want.
You can make the biggest market research ever imagine for your business by reaching as many people as possible and sharing the questions, they don't need to have you their contacts but they are still able to answer your questions.
This will create a whole new level in the way marketing is done online. Like we have been saying for a long time now... the news, services and businesses will find you, no longer you will have to look for them.
How will this affect Facebook or Twitter? That is only to be seen, all the attention is going to how Facebook will react about Google+ but what about Twitter? While not having all the eyes on them we might be giving the space they need to be the real threat to all social networks around.