I can see his uses, but is a pretty big points sink for not much payoff in my opinion, especially if you aren't giving him a magic weapon.
Warboss: Great Weapon, Light Armour, Shield
Pretty essential, good choice. A magic banner wouldn't hurt
Big Boss: Light Armour, Shield, Battle Standard
I love having expendable shamans. I took 3 in a previous 800pt list and they did me proud. Just having one is going to bite you in the ass if you roll a bad spell however.
Night Goblin Shaman
Fair enough. Depending on who you are against, I don't know if netters are going to be worth it. No fanatics seems odd, considering they are your only big frontline.
40 Night Goblin Spearmen: Netters, Full Command
I am pretty split about this. In my opinion, the range of short bows and the innacuracy of goblins doesn't justify taking a small unit of them. The only reason I would take goblin bows would be in a big unit with the Spider Banner and a Shaman to buff the poison, but it is a matter of taste. I am also slightly confused by the fanatics, considering you should be protecting your ranged units with your other units.
20 Night Goblin Shortbows: Musician, 2 Fanatics
I don't really like trolls at all. They are hardly stronger than Orcs, with many more drawbacks and higher points. I guess if it is a night goblin army they fit in, but I would perhaps consider using the points for mangler squigs or war machines.
I haven't used squigs in a long time, but they still remain a pretty potent shock unit for their points.
15 Squigs 5 Squig herders
Overall, a solid foundation, but you are spending points in fairly odd unit choices. I would suggest dropping the warboss in favour of perhaps more shamans or a great shaman. Perhaps shift the fanatics to the spearmen.
I also must put in a word for goblin wolf chariots. I ran an 800pt list in a tournament with 2 units of three of them in and they were wiping out entire units just through impact hits. I ended up coming 2nd in the tournament out of about 30 people so I would highly reccomend them!
Anyway, good luck with your list! I love all Night Goblin armies and I am working on one myself at the moment, so keep us posted!