It's pretty dang awesome now it's all working OK. I have spent the last two nights on it with my mates and I think it's brilliant! The variety of missions is incredible, I think they have really done a good job of the multiplayer and it's not often games like this work well with multiplayer, in fact I cannot name one I have enjoyed.
Last night 4 of us setup a crew, did about 20 missions and every single one was different. The screen when choosing missions is really well laid out, shows exactly what you can do and what it will entail. Then if you're bored of doing missions you just go into free roam and walk about doing odd jobs, buy yourself somewhere to live etc.
To the person above who said 16 would be limited, I think it's a good number as anymore and it would be crowded. There is already a hell of a lot to do, when you walk down the street you might get a random event start that you can get involved in or someone may invite you to a mission they are about to start etc.
I think the apartments thing is really well thought out, 2 of my mates have bought them now and I am hopefully going to get one tonight