First there was the iPod, now there's the iPad? I guess next they'll make one that can walk: the iPed.
Don't forget the tasty one you can chew the corner off when you want something sweet - the iPud. I didn't see Pocket (or S&S) mentioned as signups on the original iPad presentation, so have to wait and see when it's out. However one thing is clear - the Bookstore is regional, so is going to be bugger all use for those outside the states.
I keep hearing over and over that "most" applications that work on the iPhone will work on the iPad. That probably includes the Stanza, eReader, BookShelf, and Barnes and Noble ebook readers. I also read yesterday that Amazon is specifically planning an iPad version of their Kindle software. And, finally, it would surprise me greatly if S&S books are left out of the iBook store.
You can get iBook and possibly Star Trek books from Apple's iBookshop. There will be Kindle for iPad so you can get Star trek books from Amazon. And there is the txtr app which may or may not work on the iPad and if it does or an iPad version comes out, you can then get any Star trek in ePub (except B&N and Apple) to read. Also, if you strip the DRM from Star Trek in ePub, you can load it on the iPad and read it with iBook. So your answer is yes. Just no need to have to have iPad specific versions unless S&S is going to support iBook.