I feel like I may have coined my own terminology so let me explain.
This person needs to be passionate about not just the platform but also the industry that it is based around.
They own the project, and nothing gets by them. Also they are heavily involved in the creation and design of the system. The buck stops at them for what goes in and what doesn't. They say yes or no on a feature request. They decide which language to code the solution in.
All the coders report to them. They could potentially hire/fire people. However they also code the important parts and look over all critical code.
The whole project rests on their shoulders and they are responsible for success and failure. A critical part of the job is long-term, leading the design and chosen focus into the future towards business growth and customer happiness.
Who is this person (job title?) and what can be expected from this job? What about compensation?
I THINK MAYBE I FOUND IT: http://www.developer.com/java/ent/article.php/3529081/Anatomy-of-a-Software-Development-Role-Development-Manager.htm
...but I'm still reading ;)
UPDATE: Yeah...
"The development management role is the role whose purpose it is to keep the vision on track. This is much like a CEO, who sets the vision for an organization. This of course differs from the COO, who-like a project manager-ensures the day-to-day operations. While it's the project manager's goal to get the project to the finish line, it is the Development Manager 's responsibility to look ahead to make sure that the finish line is the right finish line to be reaching. While the project management position is a management position, the development manager role is a leadership position. Click here to see how the the Deployment role fits within the full organizational chart."