A few places I like to look for information, news, interesting stories etc. about Korea (and Asia and the world more generally) include:
The Nautilus Institute: A good collection of policy-wonk stuff on contemporary Korea, northeast Asia etc. Especially good on security and energy. If you want to receive a nice daily digest of Korea (and Asia)-related news, subscribe the the Institute's NAPSNet Daily Report.
Frog in a Well: Korea: History-oriented blog. Not as much participation as some but usually worth a look.
The Marmot's Hole: a blog written by a collection of largely expats living in Korea. Interesting stories and commentary on contemporary Korean culture, politics etc. etc. Warning: some of the postings veer off into the irreverent and inappropriate (especially from a family or BYU viewpoint). Still, on balance, a good place to keep one's finger on the pulse of contemporary news stories and issues.
The Useless Tree: Not specifically Korea-related but a thoughtful and fascinating exploration of how ancient Chinese philosophy and thought can speak to issues of today.
DPRK Studies: on again, off again blog devoted to North Korea.
NK News: Especially useful for its searchable database of Korean Central News Agency (KCNA) stories.