The layout is slightly different--tabs are the topmost element, followed by the toolbar dominated by the address input area, and then the bookmarks toolbar. Visible controls are minimal compared to a stock Firefox but everything necessary is available either through the tools button or with a right click. Most things work well.
Spellcheck is awful, with some quite common words missing from the dictionary. The suggested replacement feature is the weakest I've seen in 10 years or so. For some reason opening a PDF just takes you to a blank page--to actually see the content you have to download the PDF. I've had one web page that Firefox loaded fine, but Chrome would load, then replace with a "Oh Snap" page.
One of the nice features is a task manager for the browser itself. Shift+Esc will bring up a window showing each Chrome process (each plugin and tab uses one process) with the memory and CPU usage for each. This is nice in my case, because Flash has been slightly unstable on my Ubuntu and hardware combination for the past few versions. losing sound after many hours. The task manager lets me kill just the flash process without affecting anything else.
On a netbook with a small screen, Chrome is a contender--the interface makes maximum use of real estate with few compromises. On a bigger screen, I think I still prefer Firefox by a small margin--that may change once Chrome is polished a bit more.