"Killing deals" was certainly a significant topic when chatting with other bloggers (though I don't believe there was a presentation on that). I didn't hear anything about the latter issue.

The impression I got from other bloggers is that on the whole, they take "blogger responsibility" quite seriously, while trying to balance the fact that as a blog, we are inherently in the business of writing stories. Deals are obviously a big story which bring lots of readers. I think a large message from the conference was about attribution, which applies to deals. I think the prevailing view is that if: (a) the blogger found the deal alone, it's up to them to do what they want with the content (yes, someone else might have also found it, but it's a big world out there!), or; (b) if the deal is already published on the internet in a public way (FT, Reddit, etc.), it's free game, as long as you attribute.