Maybe I am not as heavy a Twitter user as other people here, but I hate how easily I can miss important tweets if I just don't check my feed for a few hours. Since I am also on a different time zone than many people I follow, I end up having to catch up on hours of tweets every morning by scrolling down the page for ages. Otherwise, I can easily miss extremely relevant/interesting things.
If this feature allows me to quickly get an overview over the most interesting tweets (and I can turn it off when I am following the feed more closely) that's great!