I haven’t seen anyone using their old logo. All the articles and thumbnails use the new one
Edit: I was wrong, clearly the old logo is still being used! It’s not as far as the original reply indicated though, I’ve still seen a majority using the new logo (unless your primary metric is thumbnails on lemmy)
Go to watch all the articles on the verge, Engadget, the videos posted on this subreddit, they all had the old logo. This post is also using the old logo