Too be honest, a lot of people overlook hub pages. They write several hubs and don't make anything or don't make much, but what if you took all the niche blogs/sites you have made. And assuming you write decent sized post had posted those blog/site articles as individual hubs. Some people would have hundreds or thousands of hubs. Now lets take those hubs, and say you write 1 ezine article per hub to promote it.... now I know it all sounds time consuming but, couldn't you make a decent amount of money doing this ?
I look at the top writings on hub pages who have hundreds of hubs, and so many followers that there hubs get ranked up to page one of "best" on whatever subject they write about. I've had a subject be ranked #1 on best and I didn't even perform any seo on it, and I made almost a dollar a day. Now you laugh but theres people with 500+ articles all ranked best and some on the front page as best out of all categories. Now assuming those people do write 1-2 ezine articles per hub which wouldn't be hard if you're a good writer ..... I can see HUGE profits coming from this.
I'm not saying niche sites are bad or anything, or too abandon them...simply saying I am starting to think that using hubpages/squidoo the right way and treating each hub like its own website as far as seo goes, could yeild decent profits.