I don't use a professional page, but I use Google+ for work. I deal with many companies. When I make a connection with someone, I invite them to one of my circles.
I also use Linkedin quite a bit... as much or more than Google+ actually.
Professionals want to maintain a list of professional contacts. Linkedin is a no-brainer. Google+ offers a similar, if not more casual, experience. It's a matter of how you manage your circles.