I wonder if the most obvious difference might be when not what.

Hm, I obviously can't speak for laurashapiro, but I've watched vids in BtVS fandom quite a bit more than any other fandom, so I think they'd be from roughly the same era as most Farscape vids. The biggest difference I notice between 5-10 year-old Buffy vids I still enjoy and newer vids is how fast the cutting is, but even that isn't *that* big a difference. Then again, it's possible the BtVS vids I enjoy and rewatch the most are the ones that are the most like more current vids. :D

I can't speak to the second question, about the influence of Farscape vs Xena vs Mutant Enemy shows, but I'm interested!