- Chitika might work on a health site, if the quality of the content is good enough. - Chitika is to make extra revenue next to Adsense, not a replacement for Adsense as it is still far away from the revenue can get from Adsense, especially in niches like health
Chitika is strongly not recommended. Just visit their blog and read what their old publishers saying. They comparing Chitika as Cheat
Answer For 1 AND 2 : Chitika is something like a premium ad n/w (self-proclaimed). Their high paying ads would show up ONLY for US/UK SEARCH ENGINE traffic. This mean if you're going to replace your adsense ads with chitika, u'll be losing out on a lot of potential revenue. The best bet is to save ur adsense ad code in a file on ur server and give that as the alternative ad url when u make the Chitika Ads. This way, the premium ads would show up for targeted audience and you wont lose out. PS: Chitika is better paying for technology (LCD/Cam reviews) and Finance(mortgage etc) related content. I suggest you stick on with adsense.
Chitika is better on mobile sites (how much mobile traffic do you get?). They have a script that makes the ad be prominent on iPhones & Android.
I like Chitika ad format. The only issue I feel with them is the ads audience. I am getting huge amount of traffic from non US/Canada region and Chitika is not displaying for them.
There are ads saying Chitika is the second largest income way online . first is adsense. But I dont think that is true, not from my experience. But I cant tell it for sure since I am from India.