I just had an interesting exchange with "Muchas Gracias" in the comments of this post.
In the exchange, he (she?) tells of a 10 kilometer WiFi link he helped build in Havana using fabricated antennae. He also says some people are sharing 56 kbps Internet connections using illegal WiFi access points.
In another comment on the same post, Napo tells us that WiFi registration is indeed enforced, and the authorities are working hard to detect illegal signals.
I established this blog to discuss the state of the Internet in Cuba, and hope we get other contributions telling what people and the government are really doing. Even these comments lead to other questions -- how common are shared WiFi access points in Havana and elsewhere? Is there not a danger that the police will detect the 10 kilometer WiFi link? The report I just wrote raises many questions that can only be answered from inside Cuba.