No need to release anything if you don't change anything, to comply with the GPL.
Erm, take a look at Section 3 of the GPL [gnu.org] -- it quite clearly states that if the program is redistributed in binary form, it must be accompanied by the source code or a written offer for the source code.

You may be thinking of the LGPL [gnu.org] instead, which relaxes redistribution requirements.

Score:5, Interesting