"The heart, in contrast, is a universal symbol that resonates across languages, cultures, and time zones."
I don't really buy it. Many countries have stars in their flags/coats of arms. There's no such unified symbolism for hearts. For example Chinese pictogram for heart is 心.
Maybe twitter meant "it's a universal symbol that resonates across cultures which derive from the european middle ages"
And the meaning of stars on flags is definitely not "this is something I really like." It's not a clear symbol of anything.
Twitter does a weird thing where they crop the top and bottom of photos, requiring you to click it to see more of the image. For 140 character posts, somehow the twitter design has ended up as an cumbersome and cluttered webpage.
Interesting to think about how similar Twitter, Tumblr, Facebook, and Ello are. Knowing how easily any user base can jump ship if one starts to go down, others are ready to pick up the deserters in a heartbeat.