When the MacBook first arrived I saw reports on Twitter from users experiencing poor performance with Google Chrome, which was concerning, but so far performance meets my needs.
Although I have yet to test how well this notebook can handle 5 windows with a combined 40-50 tabs in Chrome, it has no problem with the 2 Chrome windows and 10 tabs that I normally work with.
This is not a notebook that I will go to for heavy video editing, but I'm already doing a lot of that right on the iPhone or iPad.
It's too early to make bold proclamations about battery life. After 3.5 hours of web work with the screen at 70% brightness I still had 50% battery life, so it may be able to hit the 7 hour mark based on my average use.