We list this Chromebook first because it's the one most similar to the Cr-48 in terms of hardware, but with some improved specs. Essentially, if you weren't able to score one of Google's prototype Chromebooks, then the Series 5 is the closest thing to it -- for a price.
Like the Cr-48, the Series 5 has a 12.1-inch screen at 1280x800 pixel resolution, 2GB RAM, 16GB SSD, but with a better webcam that captures images at 1 megapixel (the Cr-48's showed images in a very blocky resolution) and with a slightly better battery life of eight and a half hours on a full charge (compared to the Cr-48's eight hours). The big difference is that the Series 5 runs on a dual-core 1.66GHz Atom processor, compared to the single-core 1.66GHz that the Cr-48 had (which proved to be underpowered when it came to watching streaming videos).
The Series 5 is offered either in Wi-Fi-only or Wi-Fi with 3G models. (You get 100MB of mobile data to use for free every month on the Verizon network with the 3G model.) It weighs 3.26 pounds.
Now for the sticker shock: $429 (Wi-Fi-only) and $499 (Wi-Fi and 3G). The prices bring to question whether they're worth the value over lower-priced netbooks that have stronger technical specs (like a large hard drive), or a tablet.