yes, its whitehat, all you have to worry about is bounce rate and business goals. are you receiving the targeted traffic. i am not sure, you going into vegetable market selling the computers is not at all worthy!
http://www.youtube.com/watch?v=CgBw9tbAQhU I believe what's implied here is the bounce rates from the SERPs. Google may look at what results get clicked the most, and how quickly searchers bounces back to the search results from particular sites. But if these visitors come via Twitter - what's the use?
Google bot sits on your server to check the traffic. Even if you dont have Google analytics installed, it may be checked using Google webmaster's tools. The more traffic you get... the more +ve point gets added against your URL and the better ranking you achieve in SERP. Because Google algorithm consider it as a signal of user love. And if it is from Twitter/Facebook it is given more importance as social love signal. This theory is proven by JohnChow and ShoeMoney. Hence avalanche twitter traffic is so important for higher Google ranking. Not only that, retweets against a certain term will give you better chance to appear in twitter search result for that certain term.
Facebook is for the en masse... not good for a business. For fan site and interaction purpose FB is OK. But when u r talking about social media for business Twitter is your choice. If a brand want to update its' users and they post in FB they need to wait their users to check it. But for Twitter it directly goes to follower's timeline and followers can check the posted link instantly. Image posting or 140+ character update is no more a problem on twittter with the increasing use of twitpic or 140plus.2et.in