After a few more days with the Cr-48, I've got a few random thoughts I'd like to share.
Performance of the device is not as great as you might have hoped. Pages with a lot of elements (think ads or widgets that load from various sources) load slower than I'd expect. I'm sure only having one Atom core available to Chrome is holding perf back a lot here. Something interesting that I noticed is that the Chrome task manager shows a GPU Process. I'm not sure what it's used for. Could be there simply for WebGL, but it's possible they are going to accelerate the page rendering pipeline with the GPU.
Flash performance sucks. This surprises no one. In general, Flash on Linux sucks. Flash on Linux on Atom sucks even more. It's too bad really, cause I'd like to watch video on this thing, but unless you knock the resolution all the way down it's almost unusable. I don't think Chrome OS really has anything to do with this (or that they could do much to improve this). This problem is in Adobe's hands. Thankfully, it seems that Google has been able to pull Adobe's strings to get them to care a little.
The trackpad isn't that great, but it's not as bad as some people think. Maybe I'm just lucky with my hardware, or there have been software updates to fix things. I don't know.
I mentioned before that I switched my machine to Developer Mode. Now, I've switched back. Turns out there wasn't that much going on to make Developer Mode worth it. Sure, there's a full terminal, but you can't easily install apps (in fact the root partition is not even mounted with writes enabled) or do much other than much around with the file system. So, as a user, it's not very useful. If I want access to a full Linux system, I'll install Ubuntu. That's not what Chrome OS is about, so I decided that I wouldn't bother messing around with it. So, I'm back to normal (l)user mode.