I imagine that sites akin Hacker News would arise to help filter and curate each field. They could range from highly professional, well-financed operations to a

I imagine that sites akin Hacker News would arise to help filter and curate each field. They could range from highly professional, well-financed operations to a prominent academic who catalogs interesting papers on her blog to a popularizer who focuses on exposing/explaining journal papers to a lay audience. Academic could use tools like Scholastica so self-publish in dozens of small sites free of charge - but they could also use Scholastica to replicate the 3-4 journals seen today. I don't think it's a given that a field will be harder to track - if anything, discovering great work would seem easier if more voices were able to play a role.