Do you think it will replace the shoutbox?
No, the shoutbox is way more communal than this chat.
Will it improve the nGu friend system?
I guess so, you have to add people to talk to them, other than that the friend system serves no real purpose anyway :p
Do you notice any problems (concerns , lag , glitchy , etc) .
A bit of lag at time, nothing too bad.
I think It's pretty cool, instead of hanging round the sb waiting to sbpm someone, you can just contact them directly. (+The drawing part is fun =D )