There is not a methodology present, it is only stated that Technorati is the reference and that political blogs are on top of the educational ones.
For your convenience, you can access the full list in here. Remember that the ranking number along the name of each blogs change every time. As for today, those number do not match anyome.
I said the list didn't include, at least, three blogs with high ranking on Technorati:
Free Technology for Teachers - 606
Larry Ferlazzos' Blog - 563
Stephen's Web - 512
I haven't made an investigation. This is only my first attempt to probe the list over there needs to be reviewed it. For other lists of education blogs, just click on the link.
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