flyingillini,
I think Spanish is important if you will be working with Spanish speaking patients. For me, it is extremely important, being from California and because I want to work in underserved areas. My parents emigrated from Ecuador, so my first language was Spanish and I majored in Spanish as well. Until med school starts I will continue to work as a medical interpreter for patients applying for disability or worker's compensation benefits.
I agree with what MacGyver has said. A higher percentage of people in the US do speak Spanish. Lavndrrose, children of immigrant parents do learn English, and actually, the children of first generation parents are usually no longer bilingual. In regards to your comment about the economy, according to Jorge Ramos' book, "La Otra Cara de Am?rica," the National Academy of Sciences has found that immigrants, the majority of them Latin American, contribute 10 billion dollars to the economy of the US. I think the majority of immigrants do think that English and an education is important and teach that to their children, so that they do not have to work strenuous jobs in factories, in the fields or as nannies or housekeepers.