@sedition
As far as support goes, you will probably find it awkward to buy books for ANY of the top bookstores here in the U.S. or Canada from Taiwan without jumping trough some hoops (a U.S. billed pre-paid credit card and HTTP-Proxy).
On the other hand, there is an excellent regional overdrive library located in
Singapore that you can easily join at no cost, that has literally thousands of EPUB titles freely available.
The Kobo does appear to be a really nice reader, and Kobo has already released some updates, so they do appear to be committed to making it competitive with the Nook and Sony.
The Kobo does support more formats out of the box, but the Nook is an Android device, so it will support virtually any format that you can find an app to read (including Amazon, if you root the Nook so you can load Amazon's free Kindle for Android App)
The Nook also has page turn buttons, where the newer Kobo Touch does not.
The reader that I use on a daily basis is a Sony PRS-650, it's reliable and, unlike the Kindle, I find it's built in software to be well thought out, and very logically organized.
On your point about devices with non-replaceable batteries, I agree 100% that companies like Apple, and most of the other Tablet makers, are being very irresponsible in creating iTrash devices designed essentially to wear out in a year or two at most, when the battery fails, and then force the user to choose between either paying more than the unit is worth to have it serviced, or junk it and buy a replacement.
I am a lot less concerned about this in the case of my Sony because -
a) With eReaders only requiring a charge cycle every week or two, the battery should last several years.
and
b) I have the Sony's service manual, and it looks like, with only a jeweler's screwdriver and other simple tools, the Sony's battery CAN be replaced.
So if you are willing to forgo MP3 playback, and web browsing (which drain the battery more quickly) the cycle life of the lithium cell in your reader should be adequate to last the life of the product.