I have been building a passive income business for a couple of years now - and every year I seem to get an email asking me - can you still start now - and build an online income ?
The answer is yes, and no. Yes its still possible to earn an online income - I earn money from websites every month - some of which I haven't even touched for 6 months. But what I am doing now is different from what I was doing 12 months ago - things change on the Internet and to keep ahead of the game and continue to make money you need to be continally updating and refining your methds: or as the experts say: test, test and then test some more!
One thing that does become easier each year though is that I have more and more aged sites and other Web 2.0 properties (Hubpages and the like). As these sites get old - they get more trust from the search engines. Many of those istes haven't made me much money directly - but I can now use them to link to my newer sites to support those sties. Just as in the real-world - you can never really have too much (web) property!
One thing I have noticed recently with the online business game is that advertisers are paying less - less commission and less for adwords. Most of us who use Adsense, eBay and similar programs have noticed that the payouts are becoming lower - and generally through no fault of our own. The short answer to that is "its the economy stupid" - well really the American economy because the US still controls the lion's share of the online economy. Especially for those of us who publish in English.
So yes, maybe its a little tougher to develop a passive online business of your own - but its a better option than trying to find a job in a down economy! If you are interested in hereing more of my views swing by my blog at http://lissowerbutts.com