Yeah, and Twitter is just a database of content items with a 140 character max, right?
My point is, user experience does matter...and as Matt's post indicates, they've actually solved (or attempted to solve) some pretty big UI obstacles with this theme.
Combine that with the fact that I could probably have this up and running in 5 minutes or so and I think they've definitely accomplished something pretty cool here.
Don't get me wrong, I really like what they've done, but it isn't mind blowing. The design and user experience are stellar. It's amazing how the guys at Automattic can take an old concept, pare it down the the minimum viable product, and polish the hell out of the experience.