Just wanted to share this as I've been forever waiting for a reader that would integrate Dropbox 'out of the box'.
I'be had a play around with the Kobo and the iPad app of the same name to see how they behave with each other.
Using dropbox on the ipad with the app is super simple but of course epubs don't sync between devices, no surprise there though I'm hoping a future update may change that. So I set about visiting the Dropbox site from the Kobo Touch browser and it turns out I was able to download an ePub to the reader without a problem from there.
Navigating to the file was somewhat fiddly but it worked!
I guess it makes perfect sense since epubs can be downloaded from sites offering free ebooks but I still felt it was worth sharing as I have not seen this mentioned anywhere and I think this makes the Kobo touch the only e-ink device capable of doing this without hacks.
Hope it helps others looking for this kind of functionality.