The site which earns good with Adsense is.... Google Adsense it self. But, if talk about niche then it is forex, make money online & web hosting.
i think sites with financial and medical niches earn the most coz of the money generated per click....... constantly bidding is goin on particular keywords so the cpc goes on increasing
It really depends on your meaning of the "most." If you mean the most overall income then you are going to be talking about huge authority sites with high PR in most cases and 1000s of visitors per day. If on the other hand you mean the "most" for the time invested micro-niche sites do very well often earning $50-$100 a month for just a few hours work.
He asked what site is earning the most. Not "What kind of site". I think the answer to that may be a hard one to discover but I know of several that earn $100,000+ per month
Sites with lots and lots of high quality original text based related to a good niche content earn the most
Again, I see the question being what site owns the "most." You are welcome to your own interpretation of the question but I personally view a site owning $50 per month for 3 hours of work a better investment than one earning $1,000 a month on 1000 hours of investment. Its all in what you are looking to achieve. There are plenty of people making healthy 6 figure incomes with a few hundred adsense sites. I don't know of many people making 6 figures or more with 1 site from adsense. They exist but they are few and far between. -James
Making money with anything online is more about total traffic and your CTR than how much you get per click. Concentrate on the traffic. Just my 2 cents....