BEFORE PLAnnING TO START A MONEYMAKING WEBSITE..

What you should keep in ur mind b4 starting a website or a blog is the present demand.
You may take some time to study about the demands and needs of the browsing population, through other sites or blogs.That is very important in order to get a good traffic which is the most important factor of a good site.Then you may look for the adsense and other money making schemes.
Then the next thing is that ,you should be ready to devote your time for ur site. ie for updating and regularly stuffing ur site with factors that will retain its regular traffic and which can attract more new traffic.
The most important thing that shud be always in ur mind is that no one can become a BILL GATE in one day, neither in one week...It compulsorily demands ur time and hard work.So you should work.Whether its a blog or a website,or a pay-per-post scheme or a pay-per-discussion..it demands ur time.
After having done your work ,then allow the ads and the traffic to do their's.
SO ALWAYS BE THERE FOR YOUR SITE.... :)