re: Large Files... there's no reason the files have to be transmitted to the server anyway, the app could access local storage just fine. This probably indicates that the "save" paradigm is broken, and instead we'll need to start thinking about how to present "local save" to "cloud save" to users.
On Peripherals – Google is already addressing that problem with Cloud Print right now. The same concepts could easily be translated to other peripherals. Anyone whose tried to use it will tell you the concept is very rough right now but it has promise and several companies have agreed (in theory) to support it in their hardware with future versions.
On Large Files – I don’t know of anyone who doesn’t think our current bandwidth is just a fraction of what will be available to us 10 years from now. For video editors who need to use raw files I don’t think Chrome is appropriate but Google’s said as much by targeting the OS at the netbook/low-end notebook market to start. Again the point is to refine the OS through iteration (as Google does with all their products) so when editing video in the cloud is a possibility they'll already have the most refined OS for it.