ACS News Service Weblog
The American Chemical Society News Service Weblog is for journalists who cover science, medicine, energy, environment, food, and other chemistry-related topics.
http://acsnewsservice.typepad.com/acs_news_service_weblog/

Chem-bla-ics
This blog deals with chemblaics in the broader sense. Chemblaics (pronounced chem-bla-ics) is the science that uses computers to address and possibly solve problems in the area of chemistry, biochemistry and related fields.
http://chem-bla-ics.blogspot.com/

ChemBark
ChemBark is a blog about chemistry, but not as technical as other blogs
http://blog.chembark.com

Cheminfostream
News and views from the world of chemical information, modeling and informatics applied to drug discovery.
http://barryhardy.blogs.com/cheminfostream/

Chemistry World blog
This blog provides a forum for news, opinions and discussion about the chemical sciences.
http://prospect.rsc.org/blogs/cw/

Depth-First - Walking the Web of Chemical Informatics
Depth-First covers cheminformatics from the perspective of a synthetic organic chemist turned software developer. Topics covered include cheminformatics Web development, object-oriented programming, Open Source software for cheminformatics, Open Access, and user interface design.
http://depth-first.com

eCombiChem Leads
This eCombiChem Leads Blog has been created to provide news and views from the world of combinatorial chemistry.
http://barryhardy.blogs.com/ecombichemleads/

Heterocyclic Chemistry
This blog deals with the syntheses and the functionalizations of heterocyclic rings (mainly 5 and 6 membered rings) by either unusual way, or with scalable procedures and in a straightforward manner.
http://hetchem.blogspot.com/

Mass Spectrometry Blog
A web log of mass spectrometry web sites, discussion groups, mailing lists and other links and items of interest to the mass spectrometry community.
http://msblog.kermitmurray.com

Molecule of the Day
This site is by a chemist who enjoys rambling about the relationship between chemistry and real life to non-chemists.
http://scienceblogs.com/moleculeoftheday/

Org Prep Daily
It is a blog with synthetic procedures. From the way it is written, any competent organic chemist can tell that the information is self-consistent and of high quality, with enough information to repeat the experiment and confirm that it worked.
http://orgprepdaily.wordpress.com/

Organometallic Current
The blog Organometallic Current is created for chemists to discuss and share their comments on current topics in the field of organometallic chemistry.
http://organometallics.blogspot.com/

Sigma-Aldrichs' ChemBlog
ChemBlogs is designed to be an open forum for the global chemical community, with posts written by Sigma-Aldrich personnel and invited posts from leaders in academia and industry. Sigma-Aldrich will initially highlight topics directly related to catalysis, and future plans will include expanding posts into diverse areas of science such as materials science and chemical biology, thereby effectively covering additional synthetic transformations mediated by unique reagents.
http://www.chemblogs.com/sial_blog/

The Sceptical Chymist
The Sceptical Chymist is a blog by the editors of Nature and the Research journals - and a forum for our readers, authors and the entire chemical community. We'll discuss what's new and exciting in chemistry and chemical biology, be it in our journals or elsewhere.
http://blogs.nature.com/thescepticalchymist/

TotallySynthetic
An impressive blog for natural product synthesis by Paul Docherty, a Ph. D student at Clare College, Cambridge. This blog has regular comments on synthesis papers (ca. 1 per day). There are between 10-20 useful comments on each from the blogosphere. Every month there is a vote on the best synthesis.
http://totallysynthetic.com/blog/