http://www.physorg.com/
http://esciencenews.com/
http://www.sciencedaily.com/
http://news.bbc.co.uk/2/hi/science/nature/default.stm
I also go to New Scientist but the site seems to be down right now.
Space links:
http://www.universetoday.com/
http://www.space.com/
Science blog:
http://www.ox.ac.uk/media/science_blog/
Any other good ones I missed? What is your favorite?