I've put up 12 articles on Web 2.0 properties such as Vox, WetPaint, HubPages etc. Just about all of them are indexed by now but not even showing up in the SERPs.

My landing page is #59 in my niche which is fine for right now. None of my Web 2.0 props are ranking and they don't have duplicate content. I did summarize or spin each article so that they are not the same. However, my URL is the same - for an example - for Vox, I would have abc.vox dot com - for wetpaint, I would have abc.wetpaint dot com - and so on. Is the reason why I'm not ranking w/ my Web 2.0 properties is because my url is really the same - even though my content is spun?

btw...I'm just aiming in one niche, so I'm really concentrating on a three word phrase as my KWs (at least on my Web 2.0 Props).

When you say they are not showing in the SERP's how long has it been? Have you tried searching in Google for your "Title of your post" In hyphens "" ?

Also make sure you use a browser with no cookies else Google will deliver you inacurate results by delivering you pages you were last on.

You should also try searching in Google for certain parts of your text from those articles again in hyphens like; "a random peice of text taken from my article"

Search like that and if Google finds the articles you know they are indexed.

I would say you are worrying about it too much. You've done your work. Now just keep on marketing and promoting and working on new things and ways to get traffic to your site. Don't spend too much time on one thing. HTH.

Maybe you have to rewrite more words and phrases on it. Since this articles are really alike, and there are three of them. Plus you even use the same for the urls.. making it more harder for you to make it look different from each other.