A last word (at least for now) on MPF's:  What exactly do they do?  Most are in IT and knowledge management, with an increasing number in marketing.

"Marketing" remaining a fighting word to some, however, the commitment to marketing varies greatly firm by firm.  Slaughter and May, for example, a famously conservative firm, has barely one-third the marketing personnel as does CMS Cameron McKenna (a firm of similar size), and one-fifth that of Allen & Overy.  And, despite a recognition that marketing is here to stay, even on the part of "antediluvian" partners, the firms themselves admit their marketing efforts are unsophisticated. 

Wouldn't it be fascinating to see a similar study in the US?  Would firms cooperate in revealing meaningful data?  What if they were promised the full, detailed results if they did?  I think an enterprising editor—or author of a blog—might well take up this challenge.