The project proposal (~2 pages, 11pt or 12pt font) should include the
following recommended elements, or be similarly substantive.   
By "be similarly substantive", I mean that the proposal format is somewhat
flexible, if a team feels the need to deviate from the recommended elements.
I ask for 2 pages to make sure that teams are entering into this with 
their eyes open, and not just putting a few catchy phrases into a file 
without thinking through the project execution.   The ~2-page proposal 
length gives enough meat for me to understand the scope and difficulty of 
what you are proposing, as well as a means of assessing the amount of
thought put into the project choice.

1. Title + Abstract.  Tentative project title and 60-200 word abstract 
(kind of a "30-second elevator pitch", written out).  

2. Team.  Who are the members of your team?  Give any relevant background 
or experience. 

3. Motivation.  What need is filled by the project (other than passing
the course)?  Why do you consider the topic area, and the project in
particular, to be interesting, significant, and/or challenging? 
What impact do you think your project can have, if done right or with
the right follow-through?  What considerations led your team to the
current definition of project scope?  Why is the project a good fit with
your team?

4. Specific Expectations.   What do you expect to accomplish during the
quarter as you work on the project?  What are specific questions that you
expect to answer? Specific deliverables or development goals?   Expected
end state of the project?  Etc.

5. Partitioning + Teamwork.  Some idea of how you envision partitioning of
the project work. (And, if available, a mapping of partitions to team members.)
As an example, for a "new Web2.0 product" project, the partitions might
include product definition, market and competitive analysis, foundation
technology investigation, intellectual property landscape, business plan,
website mockup, etc.   For a "why I chose UCSD CSE recruitment video" project,
the partitions might include investigation of available recruitment materials,
setup and conduct of focus group meetings (department staff, high school
seniors, peers at UCSD), documentation of product requirements (media player / 
browser / bandwidth compatibilities, copyright constraints, playing time, ...),
writing / storyboarding, video/production work, etc. 

6. Additional Background.  E.g., references that you've found so far.
Ideally, not just a bunch of links but also including some commentary.
Think "annotated bibliography".