Is there any? I've been "tweeting" some blog updates, and I've picked up some followers. A few I'd like to return follow because they are into what I'm into. Then I have others that are following 8k people and have 6k followers that just blab and forward news items. Would I still follow them from a marketing perspective and to return link juice so to speak?
That's an excellent question, and you will get many different answers.
If your posts are primarily promotional, I'd follow back anyone who wasn't a total spammer. Build your numbers. But, the danger is that you'll have a bunch of followers who are paying no attention to you and hence are of little value.
Interacting, cultivating influential pals, etc., can help your exposure. Same as with blogging, only shorter and faster.