It's too bad, because even though Tina's supposed to be with Artie, she had about 100x more chemistry with Mike in that 3-minute dance number than she's had with Artie in the last 19 episodes. And it's not because Artie's in a wheelchair. It's because their personalities are so awkward together. And Harry Shum Jr., who plays Mike Chang, is really such a better dancer (he's appeared in the triumvirate of modern street dance movies: Step Up 2: The Streets, You Got Served, and Stomp the Yard).
I just spent about the last hour playing the dance sequence over and over again, so charmed was I. You can catch the full episode ("Dream On") on Hulu, of course. The good news is, having shone in this episode, Mike Chang will get more of a storyline in future episodes!