foo.sh

#!/bin/sh

today="$(date +%F)"
for f in followers friends; do
    case "$f" in
        followers) q='.users[].screen_name';;
        friends) q='.users[] | .screen_name + "\t" + .name';;
    esac
    twitpull -v "/$f/list?count=200" "$q" > "$f.$today"
    wc -l "$f.$today"
    diff -u $(ls -rt "$f".* | tail -2) && rm "$f.$today"
done