Just restart your Steam client and SiN will automagically get patched. The following issues and additions were included in this patch:
- Added three new Arena Mode maps (The Pit, Behind Zee Beaker, Vertigo)
- Added confirmation prompt when deleting Arena Mode scores
- Added opt-out stats collection for the regular campaign on the main menu
- Added foreign translations for Arena Mode dialogs
- Fixed issue where all secrets could not be collected in final map
- Fixed issue where context look triggers could get "stuck" and the context look icon would appear for the remainder of the level
- Fixed issue where Arena Mode rounds would end approximately 2 seconds too early
- Fixed issue where players could be killed after the "Game Over" screen in Arena Mode