Clients expect information, quick follow up, an industry expert, and a good deal...but not necessarily your friendship.
Trusted Adviser
When I look back at those parts of my career that involved providing professional services, I shudder at the amount of time, energy and money that was devoted to such activities as networking, schmoozing, making nice, doing lunch...and so on.
No, I'm not a curmudgeonly recluse...I really do enjoy people.
But I prefer socializing with people whom I have things in common and whose company I truly enjoy.
I have done more business networking...aka socializing with prospects, clients and contacts..than I can remember, or even care to admit.
Not Necesarily Best Friends
As a provider of professional services, I saw my role as a trusted adviser to my clients, not necessarily their best friend. 
These 2 roles are not always interchangeable.
In marketing personal and professional services, of course it's important to be friendly to everyone we meet.
It's also important to remember that being a friendly...and even helpful...trusted adviser does not always mean being a best friend.
In seeking a trusted adviser, I expect information, quick follow up, an industry expert, and a good deal, period.
For friends, I prefer socializing with people whom I have things in common and whose company I truly enjoy.
It's interesting how social networking has clouded the professional/personal role. I Have had clients with whom I've clicked who want to be facebook friends. As facebook is a place where I share "personal" information, I would prefer not to mix the professional with the personal until after the transaction closes. At that point, I welcome them to my personal world....
Thanks!
Diane