It partially depends on how you get your traffic.
If you plan on getting just free search engine traffic, it takes some doing to end up with a site like Casinomeister. Nothing is going to budge that site, and he doesn’t have to look at any SERPS. He could care less about PR or links. He just links to a few sites he thinks are good for players.
That is because the site is mature, and it has lots and lots of good content. He does very little SEO and doesn’t need to. The site stands on it’s own merit.
To have a site like that takes time and work, but once you achieve that status and you are in a routine of how you maintain that status you pretty much have it made.
It is impossible to make many sites like that at once, there are not enough hours in the day.
If you are in it for the long haul and you want to make decent money, that is one way to go.
But – what if something should happen to that site? So you need backup. Create some smaller sites, let them sit out their time in the sandbox, add a little bit to them once a month or so, just kind of take it easy so that you end up with a number of small, mature sites that are looked upon favorably by the engines and are in a group of slow growing, reliable sites. You will eventually make some money off them, but most importantly they will be there for you to use and expand quickly should something happen to your big site.
Or you could decide to sell your big site and build up one of the runner’s up, then sell it etc. There is good money in that, too.
If you have decent amounts of money you can invest in buying traffic, you can go with the business model that has a lot of smaller sites and purchases traffic for them. Instead of working on SEO and content you will be working on finding good traffic sources and buying quality traffic.
All these things mentioned in this thread work for people. They are just different business models. There are people with 100 small sites making great money, and there are people with one large site making great money, and everything in between.
So where do you think your strength is? SEO? Creating content? Scouting out traffic sources? Or is it creating and buying good domains and just parking them with PPC places for revenue?
Is there a topic you feel excited about and would like to create one great site for? Are you really just interested in the money?
You need to find the spot that is right for you. There is no right or wrong, it’s just a matter of what sort of work you want to do.