I find that too many updates will turn off your fans. 6 updates per day might be a little high. Perhaps you might try an experiment, cutting back to only 3 updates per day (morning, afternoon, evening).
If the updates are done via RSS would you say they are personal - or are they more along the lines of press releases/news?
I have run several FB groups/accounts and I find the only way to get a better level of interaction and more members is to personalise the whole experience and interact with the members... ask questions, run competitions, post relevant topical news stories...
personalise the whole experience and interact with the members.
Yes, that is the kind of activity that puts the "social" into social media.
For site owners who have been strongly involved with getting convevtional search engine traffic, it is a different mode of operation. But it is a very human form of marketing and I feel it's a delightful marketing change from having a single-point focus on tweaking pages and getting backlinks.