I have a list of links to other blogs at the bottom of this site. Most of them don't need an introduction. You will probably all know Bubblevisor, LeContainer, BikeExif, MotArt and Ottonero.(and most other links the list).
Some of the lesser known ones are really worthwhile too though. MotoMucci had his CX feautered on BikeExif only recently. Clearly a talented builder and all posts are of high quality.
Motopreserve is a blog by a guy from New York. What I really like about his blog is that he doesn't pick photo's form the net to repost them, instead he creates new content by writing some really interesting pieces.
GragageProjectMotorcycles is an Australian based blog. Again, only quality stuff gets posted here, including their own very cool builds.
And the most recent addition to the list: CaferacerBerlin. A German blog and another (you see the pattern?) blog that creates his own content by shooting photo's of bikes and objects in the streets of his home town Berlin. A refreshing new blog.