I know that this post is old but I am a person who is graduating with an MSW in May 2010 and hopefully continuing on to a doctoral degree in a research & policy field. For this reason, I think I have some valuable insight.
I went into social work as a field b/c of my interest in community based work and social justice issues. I chose not to attend an expensive school but instead went for a state college. The trend in social work at MANY institutions is towards a more clinical focus. Also, the shift in jobs is going this way and I have been told by my advisor who is an admin. at NASW in my state that I could maybe find a "mixed" clinical/policy job that would become more policy with time. For all of these reasons I decided to pursue doctoral study and I have gotten a good response to my apps so far.
Here are some golden rules:
There is close to NO FUNDING available in the US for an MSW.
Private schools are not always the best schools in this field. In fact, historically public MSW departments have been stronger.
Go where you can get the bang for your buck. If you are seriously invested in policy work, you might be in for a surprise.