Printing money
Key questions: are those numbers real? how big is the market? can your team execute the growth plan?
Most important slide: valuation

Promising results
Key questions: can you monetize that traffic? (or drive traffic to that profitable destination?) do you know why you’ve achieved those results?
Most important slide: hockey stick

Micro-scale results
Key questions: who is the customer, and how do you know? what is the potential market size? what are the business economics?
Most important slide: lessons learned

Working product
Key questions: what does the product do? what’s the launch plan? who’s on the marketing team?
Most important slide: live demo

Prototype product
Key questions: what will it take to ship a working product? how do you know anyone would want it? who’s on the engineering team?
Most important slide: demo (if the product solves an obvious problem), engineering resumes (if the product is nearly impossible to build), “day in the life of a customer” (if neither of the above)

Breakthrough technology
Key questions: who owns the patents? can we make a product out of this technology? are there any good substitutes?
Most important slide: barriers to entry

All-star team
Key questions: has the team made money for their investors in the past? are they domain experts? are they committed to an idea in their domain of expertise?
Most important slide: problem we are trying to solve

Good product idea
Key questions: what kinds of risk does this company need to mitigate (technology risk, market risk, team risk, funding risk)? is it a revolutionary and novel idea? is this team the one to back? can the team bring the product to market? who is the customer? who is the competition? will they fail fast?
Most important slide: about the founders

From: http://startuplessonslearned.blogspot.com/2008/10/hierarchy-of-pitches.html