I've only checked it quickly today (I spent the full day at home, and I much prefer to play when on the go), but based on that it's totally cute! As I wrote in the other Pokémon Go thread, I've been wishing for such a feature for a long long time now, basically ever since the game started. Pikachu was my starter, and, knowing Pikachu's nature, I found that he isn't walking with me to be a missed opportunity on the developers' side. When the buddy system was introduced, I, again, was hoping that buddies will actually walk with us, so it's good to see this finally happening. I'm currently walking with Togepi, and I find him running around me to be insanely cute! That said, he wanders away a bit further than what I like at times, and since the Pokéstop next to my house was occupied by Rocket leader Arlo when I logged in today, and it was a little concerning to see Togepi running around him, I turned the game off after a short time
I can't wait to try this feature out on a day when I'm actually going somewhere and not just standing in one place