IIRC from the annotations (it's been a while), Vinge did not intend that Twirlip was right about everything; Twirlip was merely meant to a representation of the weird things you used to get on Usenet. But it worked out fairly well. (On the one hand, this might technically be a spoiler, but on the other, I think in practice even knowing this tidbit won't actually give anything away.)
(I'm glad someone linked to this. I actually bought the annotated edition a while back and was reading it back in the Palm Pilot era, I think, but I've lost it and never quite finished it. So I'm happy to see it and have no qualms for myself about grabbing it.)
I'd be pretty comfortable advocating for (metaphorical) Death of the Author on this one if this weren't, you know, a thread about the literal death of the author.