What is the general opinion about publishing someone else's RSS excerpts/headlines, without the author's knowledge or approval? Kind of like what Gregarius does. e.g: http://rss.gregarius.net. But on a site that displays ads. Is it uncool to do this? Would you be pissed off if someone did this with your feed?
Well, I don't think so, but a lot of people are doing it. So long as you don't put adsense, then you're okay. So basically, yes. You're allowed to do this and a lot of people are doing it.
Yeah, i'll be even glad if my feed was included here, specially that my site still has very few visitors And it means free backlinks too