2014-10-20 UTC
# 
tantek adactio Twitter started auto-linking (ttk.me/t4EJ8) on 2011-10-11 (or maybe 1-2 days before hand). See https://twitter.com/t/status/122781208089346048 (no autolink), vs. https://twitter.com/t/status/123862277777661952 (autolinked)