comparing: blues last.fm groups (to find artists + users)

Hi,

see one result in the picture below

also: there's now this user:
http://www.last.fm/user/blues_and_more/journal
I'll experiment more with this to find good blues artists + user libraries
if you know other last.fm groups, please share, thank you

What do you think?
P.S.
- the analysis is NOT based on group connections (which the group leader sets), but: on unique group artists (which are influenced by group members)
- the image is automatically updating
- the table is cut + shows only the top artists


(click on picture to see more)