Whether a bot logs the conversation or not, anything you say in a channel on IRC is probably being logged by someone who can then post that log anywhere they want to if they decide it's interesting enough. I don't think there's really a privacy concern with it; whether being on IRC is anonymous or not, a simple log of your conversations on an IRC channel will be almost impossible to trace back to you in the real world even by someone who knows you personally.
Somewhere around 99.99...% of what people say on IRC is of absolutely no interest to anyone outside of the people who took part in that conversation so it's not like someone would be browsing IRC files one day and stumble across incriminating evidence about someone they knew. They would have to be searching with very specific parameters to have a chance of coming up with anything meaningful, and even then it would be the original IRCers own fault for saying something in a public channel - whether they knew it was being logged by a bot or not.
However the semantic markup being used in in the few logs I took a look at was completely wrong. Most of them seem to be using <dt> and/or <dd> for each line of text. There's not much point using semantic markup if it's not going to be used correctly.
