What if Kraft Food and Procter and Gamble Merged?

As the title says, what would happen, primarily in the US, if these two companies merged.
Their market definition would probably be fast moving consumer goods.
Would that decrease of one firm affect anything in the market?
Would they become price makers?
The likelihood of collusion?
Could they have a big impact on elasticity of demand?

Why or why not would this be a beneficial merger?

Thanks for your input,

JudasQuisling