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Yes it will still be there unless the developer does not update the program to go along with the version of Android OS on your device.
Good example is iheartradio. I had it on 2.1 then when i went to 2.2 it didnt work as well. I deleted it and soon there after i wanted to add it again. Guess what, they only supported 2.1 so now it wont show up in the market at all..