It feels like everyone in a certain corner of the tech world is talking about cryptokitties. Perhaps the game is talked about so much because it is one of the few user-facing applications that has been built on top of the blockchain. Maybe it is exciting because it reveals itself as a fun use case on top of Ethereum (not everything has to be serious). This too seems right: after all, games are the things that have traditionally pushed the boundaries of hardware and software design (the need to get faster CPUs, graphics chips, displays; the need to write better software to take advantage of all that). The timing of the game also feels right: it asks hard questions about the scalability and design of underlying decentralized systems.
The thing that really stood out for me is that the game is built off cats as the collectibles. Of course, it had to be cats. It has to be some sort of internet law: at some point, everything on the internet can be reduced to or is forced to be reduced to cats: people posting them, clicking on them, watching them, sharing them. It reminded me of an excellent talk @slavin gave at Eyeo a few years ago drawing a line between toxoplasmosis (a parasitic disease carried by cats and that affects human brain chemistry), obsessive behavior and cats in art (and cats finding themselves online, posted, looked at, clicked on, sent to one another.)