Overview of Chrome:
http://news.cnet.com/8301-17939_109-10029974-2.html
Executive Summary:
It is a new browser that has been designed with a view towards modern web applications rather than just web browsing. It's biggest features seem to be around isolating web applications from each other and from any sensitive data you may have on your computer (i.e. security and robustness are priorities). It also features some technology to make Javascript run much faster than in other browsers. This will make some Web Applications, like for example GMail, noticeably snappier.
It's very much not a release quality product yet, so unless you have a reason to use it or just want to play around with it, you can safely sit back and wait to see how it develops.