Cass--do you really think you'd get an offer via a Facebook connection? Then keep the "friends", but hide them from your feed if you just can't bear it. I believe you could still get private messages from them. Same goes for, say, an ex. If you want not to see them, but want to reserve the right to change your mind invisibly, go for "hide" rather than "delete".
I agree that LinkedIn is a better forum for professional contacts--but it's harder to stay on people's radar. On FB people are posting all kinds of stuff all the time, so you're constantly reminded of their existence. On LI, if you want to remind people of your existence, you have to keep posting a status change, but since LI isn't really geared toward "streaming", your LI contacts might not appreciate getting the daily (or weekly) notification that you've changed your status.
I think in certain industries (probably marketing, for one) LI *is* used like FB, and people are posting and reading status messages all the time, but if your industry isn't like that, then trying to stand out on LI can backfire. Better to be visible by other forms of participation on LI like posting messages to groups or answering questions. Getting a weekly notification that "Cass has answered a question in the Care And Feeding Of Architects and Structural Engineers forum" is, in my opinion, moderately more interesting than "Cass has changed her status." The latter says to me Cass is changing her status to change her status (which, if you're the consultant who wrote the "how to succeed on LinkedIn" page advising people to update their statuses frequently, could be good, but in most cases probably not). The former says Cass is engaging with a network of her peers.
Just thoughts.
Hg
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