So far they have delivered on time with the Hangar Module. The dog fighting module is late, but will use their own netcode instead of the stop gap Cryengine netcode. The early previews were mostly from Squadron 42, so we know that they have that at least some working. The plan is to have the full release early 2015, but still add more content and features over time.
From Wikipedia --------------
Star Citizen is being developed using a modular approach, with the first module (dubbed the "Hangar Module") scheduled for release on or around 29 August 2013 in order to coincide with the games appearance at the 2013 Gamescom trade fair.
The initial release of the Hangar Module will allow backers of the project to explore their virtual ships from a 1st person perspective within Cryengine 3. Subsequent updates to the Hangar Module will include the ability to add upgrades and modifications to players' ships and allow players to invite friends to their hangar. The module system is intended to be iterative in nature, with updated version of modules being released as and when additional functionality and content are finalized.
Other Modules which have been mentioned by the developers (if not officially confirmed) include:
The Dogfighting Module (estimated December 2013) will allow a limited number of early backers to playtest the ship combat portion of the game against other players.
The Social/Planetside Module (estimated March–April 2014) will allow backers to experience the 1st person non-combat planet based environment, consisting of various shops and bars.
Squadron 42/Singleplayer Alpha (estimated August 2014) - little is known at this stage, but it is understood that this module will allow backers to try out the branching single player campaign (known as Squadron 42).
Persistent Universe/Beta (estimated end of 2014/early 2015) - again little is known at this stage, but it is understood that this module will allow backers to access a Beta version of the massively multiplayer persistent universe (known as Star Citizen).
Final Release (estimated Q1 2015) - Full commercial release of both Squadron 42 and Star Citizen.