Devlogs function as the mailing list for “subscribe without buying”. Anyone who follows your account will get email notifications of your updates, assuming they haven’t opted out of the emails.
Regarding polls, it’s something we plan to add for community posts, so hopefully we’ll be able to add it soon. Many people have been using a third party thing like strawpoll and linking it from their posts in the meantime though.
(Note: I know this topic is a little old, but it appears people are showing up here so I’d figure I’d leave a response)