Locals fish off it (since food is rationed and there is no seafood available in the stores).
Lovers walk hand and hand. Teenage Cubans can be seen frolicking along the way and families often enjoy it in the afternoon and evening.
There is also a four lane road that follows the Malecon having several names along the way. Where we were it was called "Avenue Carlos Manuel Cespedes (Avineda Del Peurto)". Whatever the name, it was fairly treacherous to cross.
The buildings across the street vary from "modern" several story buildings in fairly good shape to older historic ones that are literally crumbling. There is a movement by the government to restore these buildings.
My theory is it is to provide a facade to cover the decay of the Havana Centre area that sits just one block behind.
Casa1932 (where we were staying) was just two blocks from the Malecon, so it was a short walk (but death defying crossing of Avineda Del Peurto) for us to enjoy the promenade with the local Cubans.