I'm simply pointing out, as I did above, that if there were other "Nexus" devices coming, we'd likely have heard something credible of them at this point. There's no reason why the LG model would leak so extensively and we'd not hear anything
about another model. If the GNex gets a small spec bump, it'll be only out of convenience of manufacturing with recent parts to continue selling it at a reduced price.
And as far as Exynos goes... the GNex doesn't have Exynos. And you can imagine that its in Google's best interest to think about Exynos considering the best selling phones in the world run that processor.