Which way should you go? I’ll say first of all, just buy the book and I’ll be happy. Buying through Smashwords will give me a bigger cut than the other channels, but a sale’s a sale. If you’re planning to read it on an iPhone, iPod, or iPad, getting it from Apple is the easiest way to get it on there. I don’t really know anything about Kobo.
There should be more ways to buy FTL within the next week or so.