>>The catch is, it takes a lot of sites to do it!<<

No it doesn't.

>>Start off with doing the most popular. Dieting, hair loss, cosmetics, adult products (liberator.com is a biggie), plus-size clothing for women, loans, discounted inkjet cartridges (everyone needs those, and look how much those damn cartridges cost!). <<

hmmm... I didn't start off with ANY of those and after 2.5 years of doing this full time, there's only one in that bunch that I consider worthwhile.

>>Forget about those "niches" you hear about. It's crap. You can make as much money with a product that everyone and their brother is doing, because not many will buy those so-called niche products. It just isn't that appealing to most. <<

Actually, the biggest problem with niches is when every other affiliate on the planet picks them up. Until that point, niches can be very very hot... but when others pick them up, time to move to the next niche.

And now the original questioner can see the real problem with message boards... there are as many different opinions as there are affiliates.

And to the original question? It's impossible to determine your potential income without knowing your marketing expertise, the quality of your traffic, what your targeted market is seeking when they arrive at your site and what you intend to offer them.

And even if we knew all of that? Experimentation is still the only real way to determine your potential.