In 4.1, Google declared war on lag and the current software being used is pre-release. We're still another 10 days from the release of the Nexus 4 in the US, UK, etc and a lot can change between now and then and even moroe so between when the reviews went up and the 13th of November (release date). I spoke to the editor of the Engadget review (Brad Molen) and he said he'd be updating the review once it hits retail for updates and bug fixes and things such as performance improvements, improved battery life. Truth is the battery life is relative. How rigorously did the Engadget editor use it, how rigorously did The Verge editor use it? All I know is that this is my next phone and I KNOW, given the hardware, that all the issues cropped up can be solved with software, so if you're thinking about buying this phone, I wouldn't worry. When the Galaxy Nexus came out first, it was arguably the smoothest Android device of its time, but it only scored 2000 on Quadrant, compared to the Galaxy S II which scores 3000-3500 ON GINGERBREAD. The Nexus 4 should score around the same as the Optimus G (7000-8000), and probably more given it's +.2 Android version.
I know I'm blabbering on but, I may not have seen or used this phone in person, but I know it's a force to be reckoned with in an international market.