Redownloading/updating Apps no longer Available

Ok folks, I've been reading up on new features of ios 5, iCloud etc. One thing I am curious about is redownloading previously purchased apps that have been pulled from the app store. I was led to understand it will still be possible.

In my situation I back up my library of apps and music regularly but if ever needed to redownload an app no longer on the app store or no longer available on my national store (I live in Switzerland) would it be possible? Regarding the latter issue can I still receive updates for apps no longer available on my national store but available only on say the US store?

For example this seems to be the case with a game I bought back in February, Star Wars Trench Run 2.0-I d/l the latest version from the Swiss itunes shop. When looking for it I got a message it was not available on the Swiss shop but in the US one. This morning it doesn't seem to be there in the US shop either. So my question is can I redownload it even if it is pulled? Also, if it comes back to the US store but not the Swiss one and it gets updated will I still be able to get updates? Thanks in advance.