As far as the keyboard goes, on first impressions, it seems that the keyboard has no delete key or CAPS lock, but both are available with help from the ALT key. It also seems that there is no way to turn the Trackpad off. This takes about ten seconds on Google to enable debug shortcuts, but to be honest, even with the option available, I rarely use. I catch my laptop trackpad all of the time, but hardly ever on the Chromebook.
The next thing to consider is software. There's Google docs. You can waste time searching the internet for alternatives, but this means enabling Linux and playing about and it's really not worth it. I managed to get LibreOffice working but it was slow and couldn't access Drive, which is where all the files are. But Google Docs is seamless, and a lot more powerful than it looks, certainly good enough to create a manuscript for ebook or publication. It can get a bit slow with large documents, but I haven't encountered too many problems and I'm working at just over 60,000 words, but for ease of use, I chop the document into five chunks. I use headings for titles which gives me a Document Outline (same as a Navigation pane and similar to Scrivener's Binder). I also use the comment pane all of the time when editing (a recent update allows you hide comments). Getting the work out is a breeze compared to Scrivener - you just download it as the format you want.
The next advantage is the grammar checker. The grammar check in Google Docs is amazing and picks up things that other word processors miss. It is certainly infinitely better than Scrivener, so when I get to proofing, I'd have to export to Google Docs anyway. I do like Scrivener for drafting simply for the option of coloured labels, but I can live without it. The grammar checker trumps any bells and whistles every single time because I continually miss out words when writing. Even drafting, I tend to write cleaner, stronger copy in Google Docs than anything else.
So there you go. Yes, you can definitely use a Chromebook for writing novels. It's not the best solution. Hey, given the choice, I'd love a Macbook Pro, but those are way out of my budget, and probably always will be. For now, I'm more than happy with my £79 Chrome-buddy.