Alright...I think I decided.

I ruled the ED Nikkor out because of price, and because most reports say it's identical to the G. I ruled the old, 75-300 Nikkor out because it was just a touch expensive for what I think will end up a "stopgap" lens until I can afford the 70-300. So it was down to the Sigma and the Nikon G.

Both have strengths and weaknesses, and I seriously considered the Sigma (I got over my "Sigma Stigma" enough to do so). But I chose the Nikon for the reason of price - it's $150 compared to $190. That's a $40 difference. And with that $40, I can do a lot. I might even use it to get Baymen's Heritage (lighthouse) license plates for my car (which I'll have to worry about in the pretty-immediate future).

I'm planning on starting to sell some of my photos, so I can gain money from that to buy new lenses later. It still doesn't seem like the G lens is a slouch - it's not a pro lens, but it's not terrible. And if I'm dissatisfied, there's always returns.