I have always been pre-disposed to like her, mostly I guess because of her physical beauty - but she is an impressive person, and if she is able to highlight the dangers and risks associated with BRCA then that it all to the good.
Her passion for humanitarian causes is admirable, as is the work she put in as special envoy on behalf of the UN.
I have heard some medical experts cautioning against rushing in to making a decision about a double mastectomy - ensuring you are fully aware of the relative risks, what other coping and management procedures might be available, but that is an entirely sensible observation.
Her wiki page makes for interesting reading...
http://en.wikipedia.org/wiki/Angelina_Jolie