Check out the high PR Web 2.0 sites where you can promote your website for Link Building. As its just a simple HTML website to leave off your website link for user interaction & sharing. This is the simplest and the best task for better user engagement where you can follow the people according to the target country. One more thing, with this task, your two tasks are also being done, i.e. Profile Creation & Micro Blog Submission.
1) http://www.scoop.it
2) http://surfingbird.ru/
3) http://www.stumbleupon.com
4) https://www.pinterest.com/
5) https://www.tumblr.com/
6) http://www.reddit.com/
7) https://delicious.com/
8) http://slashdot.org/
9) http://www.newsvine.com/
10) http://digg.com/
11) http://www.fark.com/
12) https://www.diigo.com/
13) http://www.folkd.com/
14) http://www.pearltrees.com
15) http://www.soup.io
16) http://www.ebaumsworld.com
17) http://killerstartups.com
18) https://www.lintas.me/
19) http://1look4.com/
20) http:/cheezburger.com/
21) http://www.giikers.com/
22) http://getpocket.com
23) http://delicious.com
24) http://scoop.it
25) https://www.instapaper.com/
26) http://www.skyrock.com/
27) http://www.youmob.com/
28) http://bloggalot.com
29) http://alltopics.com
30) http://lockerdome.com
31) http://free.yudu.com
32) http://www.savenkeep.com
33) http://www.yuuby.com
34) http://in.viadeo.com
35) http://www.yoomark.com
36) http://www.designfloat.com
37) http://www.openfaves.com
38) https://www.minds.com
39) https://www.enjin.com/
40) https://www.nasseej.com
41) https://channeliser.com
42) https://vk.com
43) https://list.ly/
44) http://www.protopage.com/
45) https://www.patreon.com/
46) https://ello.co/
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