Advisory services

What are the interesting(or not) recommendation services, social media, etc. i.e. tools where the actively used data mining and text mining a subset of\ opinion mining. I want to make a collection of links. Particularly interesting projects from Russia, but surely such will not be very much. As one example:

sentimetrix.com
last.fm
imhonet.ru
vkontakte.ru (music recommendation)
iqbuzz.ru
October 8th 19 at 03:44
2 answers
October 8th 19 at 03:46
And books livelib.ru - bernadine.Wiegand53 commented on October 8th 19 at 03:49
October 8th 19 at 03:48
IQBuzz not Advisory, it service monitoring social media

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