[Updates: An alert reader pointed out that Kobo does do ebook previews---I think I just missed it. However, there's still no search and the page-turning/page number situation is still simply awful. On balance, I still think you shouldn't bother with Kobo.
On a happier note (for iBooks fans), iBooks has adopted the Nook's hold-and-swipe highlighting feature, which was my favorite thing about the Nook app. Really, the only thing I liked. Definitely no reason to even try the Nook app now. Three years and counting until Barnes & Noble is bankrupt.
I'll try to keep this space updated with new features, but probably won't.]
Merry Christmas! Several thousand people at least will be unwrapping an iOS device today. Here’s a list of the major ereader apps, and their pros and cons. We’ll see you again on Tuesday, when we go back to regular programming.
iBooks: Perfect for iOS readers
Cons: Doesn’t work on any non-iOS device. Not your Kindle, not your Nook, not any E-Ink ereader. If you want to use one of those devices, you’ll want to use a different app. There isn’t even a desktop version of iBooks, you can only use it on an iPhone or an iPad. There’s also no real iBooks website, and navigating through the Books section of iTunes is a proper pain, so you’ll need to come to the app with a title in mind.
The gist: iBooks is also the only app that will let you buy books through the app store and your iTunes account—that ability is turned off for all other ebook apps. But that ease-of-buying-books is not what makes iBooks the best ereader app; instead, it’s the fact that all the others have significant downsides. iBooks has all the core functions—note-taking, highlighting, search, dictionary, and layout options—and they all work. If your iPhone and/or iPad is your main ereader, look no further for your new favorite app.