It is a good idea to indicate that your book is an ARC, either by including it in the title or mentioning it in your journal entries. While some ARCs are very close to the final product, others may be missing important elements - maps, an index, etc. - and might be in need of another editing pass or two. It's fine to register and release them, but it is helpful to make it clear that that's what it is. [Here's another thread about ARCs that may be of interest: http://www.bookcrossing.com/---/403553/ ]
As for the global overview page - I don't think that the lack of info there has anything to do with your book's being an ARC; that information comes from the Amazon.com database, and if it doesn't have anything for that ISBN, we won't see anything here. This can change, too, as Amazon tweaks its own data - some books might gain summary info and others might lose it. I wouldn't worry about it too much!