Do you see good sales coming from it?
Did it not become profitable for you until you tracked in depth where the visits were coming from so you could block bad sites generating traffic?
Do you think content advertising can pay off in your exp?
Well content targeting does seem to convert, but at a lower rate as compared to search and might also cost a little more, since your paying for more clicks to get the same number of conversions. But then again clicks might be cheaper. Problem is that sometimes the sites the ads show up on are pretty crappy. So if its a leads or sales based campaign, end up getting clicks from there but no conversions. A lot of times ads land up on adult sites too (way too many of those around) so you have to be careful with the keywords.
Sometimes it helps though, because there might be lesser competition. Ads somehow nearly always seems to rank higher (at the same bids) on content. It's worth a short, especially if your going to track it well.