Harriet quoted the Guardian's TV Guide from 1980 (coo, I'm impressed) as saying B7 maybe was popular becuase it "lacked the moral pretension of Star Trek".
I've always enjoyed the idea that Terry Nation devised B7 as being in the same universe as Star Trek and that the Federation in both was the same, but the Star Trek version was as written by the Federation whereas the B7 version was as seen by the ordinary beings. They are both enormous Earth based federations that claim to unite large numbers of planets with diverse beings and cultures. The difference is in how they united them. A clue is the B7 Federation symbol, which is uncannily like the Star Trek one turned on its side.
-- cheers Steve Rogerson http://homepages.poptel.org.uk/steve.rogerson
Redemption 03, 21-23 February 2003, Ashford, Kent Celebrating 25 years of Blake's 7 and 10 years of Babylon 5 http://www.smof.com/redemption