Because of Susan Rice's investments in both Canadian oil companies as well as banks directly involved with the Canadian oil sands, she has a clear conflict of interest with regards to any decision over the Keystone XL pipeline. She should not be considered for the role of Secretary of State due to this conflict.
Further, given the fact that she has invested in such companies, her stance on climate change is clear, and she should not be considered for any leadership position within the administration.
http://www.onearth.org/article/susan-rice-obama-secretary-state-tar-sand...
http://green.blogs.nytimes.com/2012/11/29/stake-in-keystone-pipeline-is-...