Forums

General Bitcoin Discussion

• BitcoinTalk Forum
• Bitcoin Forum UK
• Bitcoin.org.uk Forum
• Bitcoin-Board
• Bitcoin Stock Trader
• Bitcoin subreddit
• Bitcoin Trading Forum
• Bitcoin Tweet Forum @Bitcoin
• CoinConnect
• Rugatu Q&A Community
• Facebook - Bitcoin
• Facebook - Bitcoin P2P Cryptocurrency
• Google groups - bitcoin-discussion
• Google groups - Bitcoin People
• MtGox Live
• Steam - Bitcoin
• Talkgold - Bitcoin Forum
• UgBit - Bitcoin Trading & Mining Forum

Language/Region Specific

• Australian Bitcoin forum
• Chinese Bitcoin forum
• Danish Bitcoin forum
• Farsi / Persian community
• Italian Bitcoin community forum
• New Zealand Facebook community
• Polish Bitcoin community forum
• BTCsec.com Bitcoin community forum (Russian)
• Russian Bitcoin community forum
• Serbian Bitcoin community forum
• United Kingdom Bitcoin forum
• Portugal Bitcoin Blog
• Slovenian bitcoin community
• Turkish Bitcoin community

Other

• MtGox Live Traders Forum
• Bitcoin StackExchange - Q&A site, currently in public beta
• Developer mailing list