The best replacement for forums is fora.

The best alternatives to forums are rated as following:
★★★★★  fora
★★★★★  blogs
★★★  forum
★★  groups
★  message boards
★  social networks
★  mailing lists
★  bbpress
★  newsgroups
★  boards
  vbulletin
  chat rooms
  discussion groups
  categories

Your alternative for forums is not listed? Suggest!
Speaking about forums, one probably shouldn't forget about pity.

Other search terms related to forums and their ratings are:
★★★★★ pity
★★★ joomla
★ pity voice
You have in mind a companion for forums and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of forums in all years. Click on graph for more.
forums
fora
blogs