I feel that what we describe as "soft skills" and that many people discredit, like being professional, being able to clearly communicate problems, solutions, ideas or being always willing-to learn could be better labelled as "Professional Skills".
While they're not a substitute for technical adequacy, at the end of the day, we have real people as co-workers, clients, bosses, and we provide services to them, and those skills are of utmost importance, and should be part of the interviewing process.
Also, thanks for the resources, I'll be checking them out. ;)
Couple of books I found useful :-
A more beautiful question - Warren Berger Power Questions - Andrew Sobel Secrets of Question Based Selling - Thomas Freese.