What are the uses of UG Seminar

Dear Friends,
At JIPMER, we have started a BLOG spot for helping undergraduates medical students study the subject of community medicine.  Through this medium UG students can access resources to prepare for self reading, seminars etc. http://jippsm.blogspot.com
A) What do you think are the advantages and disadvantages  of "student seminar" as a teaching method?
b) How could you evaluate the BLOG method of learning?