Not just "300" it's every single employee of Tecmo which makes up 300.
Quite amazing I must say.
Itagaki moved on anyway, even without the lawsuits, there wouldn't have been more NG.
Deciding between NG2 and GTA4 depends completely on what interests you.
NG2 has sweet gameplay, shit storyline, no replayability other than achievements and harder difficulties. No level select. Outdated engine, and the only online aspect is uploading/download gameplay movies.
It will be somewhat fantastic ride for about 5 hours, and painful boss battles. Not to mention you fight every boss at least twice, with the exception of the metal electric worm thing.
In a way it was very similar to DMC4, minus the dice roll game. Not to mention the AI is a bit more tough.
GTA4 has sandbox gameplay, which in theory is unlimited replayability. Storyline is boring to many, but it got me to beating the game, and reloading my save to do the other ending. Online with a plethora of gametypes. Downloadable content to come.
It will most likely take you around 26 hours to beat the entire story, and that's without fooling around. Of course many missions are boring tutorials, but hey you get money which you can spend on.....weapons?
If you REALLY liked NG and want another thrill, go for it.
If you've played GTA and NG and you know which one you like more, go for the sequel of that one.
If you have no idea and just want a good game, go GTA4.