"copied functions like a Facebook innovation that lets users digitally "poke" each other to get attention"
Sorry, that's not an innovation.
Facebook is all about levels of communication. You can tag somebody to draw their attention to what you've done, you can write on their wall to chat publicly, you can write privately if it's either a walled-in discussion (set number of speakers) or if it's something too sensitive to say out loud.
Poking, which I think I'm right in saying Facebook made first, is a method of bridging the small gap where you want to talk to somebody but you don't know what to say. It's the equivalent of small talk when you do it with friends: it's just a matter of alerting them to your presence. With people you don't know so well, it's even more a matter of flirtation: you don't have to explain your poke, or pretend there's a reason. All they know is that you've poked them, for whatever reason, and by doing so you've been brought to their attention.
So, if it's being copied in the exact same manner, used in the exact same way (where "poke" is an option on the level of "send message" and "add friend" on every menu), then yeah, they might have a point about copying a feature. Poking is simple like Twitter is: yes, it's basic, but what matters is implementation.
Also, regarding that site's layout: yech. It's like they took the brilliantly minimal Facebook design without realizing what made it such a brilliant design, and added tweaks to something they didn't quite understand. Sickening.