Couldn't get into the engine, felt like a head to keyboard experience with the inertia on the spacecraft being far too high. Maybe I didn't give the game enough time but after 20 hours nothing struck me as anything special...
I'd say it depends on the type op multiplayer. If the MP element is just an after-thought like in Stalker (TDM, woohoo :S ) then the single player mode is obviously better. But if the multiplayer mode allows the players to have the single player experience but with real people (OFP, ArmA, SEV, HoI, EU, Combat Missions 2 etc. etc.), then mp is clearly superior.