Much as I suspected, the reports of graphics lag in multiplayer matches on iPhone 4 were greatly exaggerated, to the point of being only distantly associated with reality
There is plenty of network lag at times, and on some VERY rare occasions slight drops in framerates, but never to the point of adversely affecting gameplay.
The fog issue, however, is, well, an issue. Opponents seem to come out of nowhere, and I suspect iPhone 4S users do have a slight edge, thanks to increased sight range.
But more importantly, the online implementation is just stellar! From killchain effects and perks and levels and tons of achievements and kill quotes and text banners that congratulate top players and statistics and career progression and weapon add-ons, to integrated automatic tournaments with rewards (something I've been hollering for in damn near every online game experience I've enjoyed for iOS)! If there is a more polished, fleshed-out, feature-packed multiplayer experience for iOS, I have yet to even suspect it exists. Even Modern Combat 3 is left behind in terms of power features (much thanks to N.O.V.A.'s integrated tournaments).
All the rest is pretty much what you'd expect. Amazing graphics for player, NPC, weapon and enemy models, bland environs, great lightning and particle effects, a story and narrative that neither touches nor engages, voice acting that covers the whole range from entertaining to annoying, well-acted and dramatic to directly painful to listen to, Gameloft's ingrained UI that might be good just because I am so used to it or because it really represents one of the best ways to to a FPS on iOS, and most importantly, gameplay, physics and controls that just feel SO right and good.
Gameloft wears the generic badge like a medal of excellence, working with polish and refinement instead of innovativity and quality of ideas. In N.O.V.A., this mindset has produced an entirely standardized and fully reiterative but amazingly polished and entertaining experience.