facebook f-list

One of my goals this year is bringing order into my life. I came across my f-list on facebook the other day and most of them, I "collectd" while playing frontierville. Therefore, I don't know them at all, have little interest in there lifes and mostly don't understand, what they are posting about. Being not somebody, that post's a lot on facebook myself, I don't see, that I will build a connection to most of them in the future.
There are even some, that post mostly in a foreign language.
I am thinking about deleting these people from my f-list...but, I don't want to offend anybody, it is not, as if they have done anything to me - it just seems all to much to me, to time-consuming. But even thinking that, makes me feel a little bit guilty.
Well anyway - I want some advice, please.
Should I delete those, I feel absolutly no connection to, and if I do this, should I announce and explain it or just delete them?