Very selective list...I will add as I go along.
Professional Watches
A blog style news site by Jason Pitsch. Good resource for news and information.
Watchmaker
Industry veteran Meehna Goldsmith's own blog, with many interesting anecdotes and provocative articles.
Hodinkee
A blog started by Ben Clymer, providing good coverage of news and informaiton.
Monochrome
Though the name sounds like a photography site, Frank Geelen's info packed site carries watchmaking stories. Strong focus on the independents.
A Blog to Read
One of the most popular watch blogs. Ariel Adams brings readers close to the watches with good reviews and news.
Watching Horology
The Watch Photography blog of my good friend Prof. Harry Tan. Also with good coverage of the horological social scene in Singapore.