Paleontology & Historical Geology
Georneys's blog "geology word of the week" talks about Nummulites
History of geology blog talks about Cryptozoology
http://historyofgeology.fieldofscience.com/2011/09/cryptozoology-and-geologists-nightmare.html
Climate
Mountain Beltway's Callan Bentley share his thoughts about climate change and reactions of american politicians about the subject.
http://blogs.agu.org/mountainbeltway/2011/09/08/a-dismaying-course-part-i-climate-change/
http://blogs.agu.org/mountainbeltway/2011/09/10/a-dismaying-course-part-ii-evolution/
General Geology
Nice pleochlorism photos and descriptions from Georneys again.
http://blogs.agu.org/georneys/2011/09/15/geology-word-of-the-week-p-is-for-pleochroism/
Magmatism / Volcanism
Cooling front sketches from Mountain Beltway are very useful to understand the formation of columnar jointing in magmatic environment.
http://blogs.agu.org/mountainbeltway/2011/08/31/columns-form-perpendicular-to-cooling-fronts/
And some very catchy field photos:
http://blogs.agu.org/mountainbeltway/2011/09/28/roadside-wonders-of-route-287/
