I just deleted my FriendFeed account. When FriendFeed first came out, it was a great service to aggregate my online activity into a single feed. I used this feature to aggregate my activity and post it to twitter and facebook.
I never really used the collaborative or social features of FriendFeed, mainly only a small subset of my social circle actually uses FriendFeed.
Now that pretty much any site, that I want to share activity from, supports Facebook or Twitter directly, there is less of a need to use FriendFeed. In addition, sharing directly with Facebook from each site allows me to specify different permissions for each activity type. For example, I can have my Netflix activity shared with my friends, and I can have my YouTube activity shared with everyone. When using FriendFeed, I can only set the permission for all activity that is share via FriendFeed.