Will incense affect other players near me?

Regular incense does not affect other players. You can use a Lure Module and attach it to a PokéStop. It does affect other players.

Lure modules attract Pokemon to the PokéStop it was activated on. These Pokemon are visible to you and everyone else near the PokéStop.

Incense only works for the player who uses the Incense, others don't see the pokemons spawned by it. A Lure module however will spawn pokemon at a poke stop that all players will see.