Netflix's "House of Cards" viewing numbers are still a mystery. Less so are its social-media numbers, according to media researchers -- which seem to be weak versus other traditional TV shows."House of Cards" witnessed the largest amount of social media activity on the day after its premiere -- February 2 -- some 44,004 mentions. But this trailed well behind traditional TV premieres: CW's "The Carrie Diaries" (174,721) and Fox's "The Following" (150,640). All this according to social media watcher General Sentiment.The company said "House of Cards" did have high "involvement scores" on Twitter. But far less in other social media areas it follows -- news and other general social-media areas.Overall, "Cards" had a 3.8 score, well behind other debut shows starting up around that time: CW's "Cult" (6.5); CW's "The Carrie Diaries" (6.4); ABC's "Zero Hour" (6.1); NBC's "Do No Harm" (5.8), and CBS' "Golden Boy" (5.0).Netflix isn't disclosing any viewing/usage data for "Cards." Some estimates are that around 2% to 3% of Netflix's some 23 million customers have seen the entire "House of Cards" TV series. Netflix broke ground by starting up "Cards" as the first big original series to appear on the subscription video on demand service -- offering a full season's worth of its 13-episodes in early February.Along with the General Sentiment, the company's MediaMatch research also shows the best matches for "House of Cards" when it comes to other traditional TV shows and marketers' brands.Best shows included: HBO's "Treme," ABC's "The Last Resort"; CBS "The Good Wife"; NBC's "Go On", AMC's "Mad Men"; FX's "Justified"; Fox's (Netflix's upcoming) "Arrested Development"; AMC's "The Killing", CBS's "Person of Interest" and NBC's "Community."Brand matches included: Netflix, IntoNow, Viacom, Aflac, ITT Tech, Zipcar, Variety, Hulu, TurboTax and Guinness. General Sentiment's volume and sentiment research comes from public online sources -- news media, social media, Twitter, among others. The volume and sentiment data is from January and February 2013. The "involvement" data is from February 2013. MediaMatch TV show and brand data as it concerns "House of Cards" comes from 6,194 Twitter users.