Good multi-player, Single player too short, Its a shame "Origin" totally screwed up the launch !!!
Single Player:-
If you want a deep complex story line then you will be disappointed. On the other hand if you want a fun (Crysis 2 meets Deus EX) shot'em up its a fairly stable game this is for you.
There are stages where you get flooded with the bad guys from all directions which was a refreshing change and the bosses with there specials keeps you on your feet.
A couple of things that I feel are negative:-
1) Its over very quickly (although I have just finished 90% of Skyrim that goes on for ever) I played syndicate on normal for around six hours which seems short to me.
2) The colour system is way to high - You feel like you have woken up with a hang over in a nightclub with the stage lights aiming at your head or driving with the sun in your eyes with a coloured bag on your head. In my opinion a more neon style game (blade runner style) effects would have worked better than loads of coloured sun flair. The effects make the game harder to play because everything blends to white.
Multi Player:-
Although I have only done a few missions, this feels more polished than the single player part of the game. All team members have to be aware of what's going on to the whole team, you will struggle (with a random group) with a man down to finish the mission.
You can heal other players (and they heal you) which gives you points (so you don't have to be rambo to get a high score), you can also res (re-boot) players that have had the hell shot out of them. If you find you are the one left behind you can limp your way towards your team mates (bashing space bar for added speed) which increases the change of coming back, instead of laying on your back, feet up, looking at the sky with several hundred bullets flying around you.
As with the single player game - you can pick up weapons dropped by the enemy and there are caskets with ammo to allow you to re-load. Enemies swarm from behind as well, which is a nice touch, and the right mouse button will allow a more detailed aim (scope or closer sights).
There is a skills tree which allows extra skills in chosen areas and you can also research weapon development (faster, more efficient, ext) these are areas where you spend the tokens earned from the multiplayer missions.
I'm sure the muli-player has loads more things I have missed out but (as you can probably tell with my poor grammar) this isn't a review from a journalist, its just my experience of the game from the eyes of a casual (but constant) gamer :0)