there already is a bot that probably already captures everything - but transcripting the conversations that go on would be a ridiculous idea IMO. as most things would be OT. it would mean somebody would have to trawl through it and find the useful stuff to post or whatever.
Not a ridiculous idea at all. I'm the channel owner of ##slackware at irc.freenode.net and have been for at least 5 years. I use an eggdrop bot to record channel discussions and I post the logs publicly to my website. I've at least 5 years of archives that people continue to search against...some even download the whole archive for their own copy. While the channel does go off-topic sometimes, the logs are still quite easy to search. These forums go off-topic quite a bit, but that doesn't hinder the search feature, does it? No. If you're not willing to search, the feature is useless, for this forum and for anything you do.
I think logging and offering the logs would be a great idea, as I know it works and is valuable.