Hi
We are looking at restructuring our company and I would like to know
if other organisations always place their product development teams
under Marketing, or whether there is a place for having a product
development strategist that reports directly to the GM and sits at
senior management level.  This would make the person more neutral, by
not being influenced by marketing and possibly better off to search
and consider all new product ideas.  Can I have any research or
company examples which do or don't support this theory.

Something to consider while you are waiting for your answer.

I've seen it all three ways:
Marketing reporting to Product Development
Product Development reporting to Marketing
Marketing and Product Development as co-equals reporting to the CEO

In all cases, the structure was less important than the disciplined
transfer from design to development.  No matter what the structure is,
if people are able to add product requirements in the eleventh hour
without changing delivery schedules, your process will deliver poorly
designed products.  (No matter who is reporting to who).  Requirements
from marketing that are perfectly acceptable during the design phase
are out of place once development has begun.

What you need is a person to discipline that process from design to
development.  That discipline must be supported by the CEO or GM. 
Without that support, the boxes and lines on the organization chart
are nice to look at, but otherwise meaningless.

Marketing should have leadership of product development.  This is
because people don't buy products or services, but their perceptions
of what the products or services might be, and marketing is the
discipline that is best qualified to understand and master this
critical perceptual dimension between products/services on the one
hand, and purchase/revenues on the other.

This is not to say that your product development people should not be
allowed to create.  As you are business, there are economic
consequences to application of effort in your company.  You need
marketing to evaluate the potential of a product or service idea
within a competitive perceptual environment, before making major
investments behind a product or service idea.  You also need marketing
to guide product development's capabilities into promising directions
for your company.

While on the surface this can appear to be a straight forward inquiry
that requires a straight forward answer - It's not an easy one because
companies have managment culture. And a company's culture can inhibit
strategically sound new product ideas capable of advancing long/near
term company growth.

As highly structured as Coca Cola is as a global firm, its been able
to sustain growth over the long haul because of some fundamental
principles they deeply believe in and execute accordingly.

1. Imagination/Inventiveness
2. Revolutionary Strategic Canvas
3. Bright Young Brains in Key Strategic Areas of of each brand coupled
with experienced leadership to understand young untapped minds
4. Pushing the envelope - new ideas are revolutionary/inventive with
imagination because they pushed the envelope and compell executive
management to THINK strategically and creatively about the Road Ahead
not the current and past dimensions of brands
5. Pin-pointing "emerging consumer targets" driven by lifestyle
spheres of influence
6. Understanding the strategic equation of "Fork In The Road" - this
is where the brand needs/wants/desires intersects with the consumer
needs/wants/desires and their is always a "sweet spot" - The strategic
question is How Fertile is it? Can we grow a business that can emerge
within our strategic principle of volume, profit, synergy with the
company's portfolio of branded businesses?
7. Company leadership (The CEO) understanding the meaning of
"championing" the heart and soul ofd the brand internally and
externally and have both groups believe in what the company is seeking
to achieve

Other compannies like Nike, Kraft, Microsoft, L'OREAL/COSMAIR, Walmart
do the above well too.

So if you're seeking to determine where new product development should
be incorporated in your company's internal structure, Marketing is the
fundamental area to anchor the Dept/Group. But like all companies, the
real pivot to address near term is company culture and leadership. 
Marketing Directors can get bogged down in budgets, campaign
developments, budget stuff and there goes those new ideas.

So the recommendation I forward to U is:
a. Estbalish New Product Development in the Mktg Dept but allow the
champions of new ideas to work independent of existing brand teams and
have them report to the VP Mktg and President (only allow the research
dept to interact as a supplier of facts/truths about category
dynamics, consumer/customer needs/wants ect)
b. Define the role of New Product Development of the company and
insure that it enhances the vision and mission statement of the
company overall
c. The leader of this area must possess must be a true "titan" of
ideation wihout fear of failure  and of  executive mgt "are U sure"
mindsets of inquiries which often times exposes their shorcomings on
their clarity on The Road Ahead for company newness. Company newness
is like refreshing air within a firm when new products are
commerically succesful and deliver anticipated outcomes. But one must
carefully select this individual. They are a very rare breed of talent
and usually have seen it, done that and are unafraid of the Road Ahead
- Why? New Product Marketers are disiplined as well as "Strategic
Adventurers" They know what to look for - smell for - listen for -
they know the Strategic Pivots that connect consumes/customers with
brands.

I found this question interesting. And the only way I could correctly
respond with an actionable comment was to say what I wrote based on
relevant experience and as a Brand Mgr and now President & CEO of my
firm BrandWorksLtd. Hope this helps...(brandworksltd.net)