I like the idea of doing both.

I like the wish list idea. How about if we make it a multiple wish list where people can add (privately if they desire) what is they want and then report on the progress and/or when it has come to fruition. Then we can really measure how effective we are and also provide a lot of wishes to a lot of people. Plus it would be really fun and interesting to see if we affect many things at once.

On a grander scale, how about targeting saving the rainforest, Aaron's city council, the homeless rate in the US or the foreclosure rate in the US (currently 1 in 7).

Cheers