In other words, the person in charge needs to manage a mature set of keywords, understands conversion, cares both about PPC, organic, email, etc. They have to help their product managers, content people, and sales people understand search, and they have to keep them happy (if someone calls from the Barcelona office and wants to know why no ad shows up under some Spanish language term, they don't spend a lot of time explaining why, they just add it to the list - because it's cheap and easier than arguing about it)
In sum: prioritization, reducing risk, keeping things predictable and integrating with other marketing efforts while keeping the rest of the company happy is their main task. Search will mature and be managed like everything else, and software vendors will have to address all the pieces.
PS. What's the hardest problem for these F500 guys? Finding good consultants who can integrate into the WHOLE marketing strategy and focus on the business value while monetizing search. If they find one, they are either hired or hard to keep interested.