That's a good start.

You have just named some article-style sites.

Does this mean you are writing unique articles for each of your accounts on these sites and including contextual backlinks?

These are great for first tier links and then you can push things like article links, profile links, forum links, social bookmarks, blog comments, etc to these first tier links for a strong backlinking profile.

You should also include a social bookmarking strategy around your main sites as well as focusing some other styles of links on unique top level domains through things like blog commenting, guest posting, press releases, etc.

There is a world of things you could be doing to push up your rankings and start targeting more competitive terms.

Cheers,
Dave

If you're using unique content on each site they will all work. There are a TON of these kind of blog/web 2.0 sites you can use if you want to make pyramids.

If you're using spun content, Hubpages and Wordpress are likely to delete it. Infobarrel also moderates them. I do find some good referral traffic to the pages being promoted on Squidoo and Hubpages too.

Here's a short list I used for this kind of stuff from a while back:
diigo.com
quizilla.com
livejournal.com
livestrong.com
weebly.com
yolasite.com
devhub.com
webs.com
multiply.com
bravejournal.com
webnode.com
ibibo.com
wiki.zoho.com
sosblogs.com
gather.com
wordpress.com
beep.com
onsugar.com
zoomblog.com/
tumblr.com/
tripod.com/
zoomshare.com/
typepad.com
ohlog.com
blog23.com
posterous.com
blinkweb.com
blogspot.com
insanejournal.com
jimdo.com/
shutterfly.com
squarespace.com/
wetpaint.com
terapad.com

Other kinds of links: Try doing some manual blog commenting on high PR pages, or even low PR relevant pages for click-through traffic. You can always write your articles for article directories and guest posting too.

That's a very impressive tier 1 sites. Mine is way different, I have my web 2.0 sites for tier 2 and tier 3 and have press releases and article directories on tier 1.