Google have already admitted that they pulled the trigger a little early on the Chrome announcement yesterday; it was meant to hit the headlines today, in fact. As of writing, the www.google.com/chrome site still isn't live, which means all we have to go on is the Chrome comic and some background understanding of Google's webapp offerings.
Gears, which has been available as a separate download for some time now, allows users to run online applications without a network connection, or alternatively speed up webapps by caching data to reduce the amount of data transferred to and from the server.
"We're applying the same kind of process isolation you find in modern operating systems" Arnaud Weber, Software Engineer, Google
Together, they add up to improved and more stable webapp performance, with better memory management that, at this early stage, sounds ideal for the current crop of low-powered devices such as netbooks. Webapps, with minimal (or no) local footprint, make good sense for machines like the ASUS Eee PC or Acer Aspire One, where onboard storage is minimal. However users still want performance and, considering their connection speed could vary wildly from a tethered cellphone to WiFi, as little network dependence as possible.
The software Google release today will be early Beta, certainly, and too early to realistically judge performance. Nonetheless, it could begin to redefine what users expect from their browsers.