I still own my first game, Pokemon Blue. Because it doesn't have an RTC clock chip, the SRAM battery still has power last I checked. In time it will drain just as my Gold version did, just at a much slower rate, eventually requiring replacement.
Glad that battery replacement hasn't been necessary since the GBA games.
Looking forward to Pokemon X and Y. White FC: 0862-2660-4156 / 3DS FC: 2492-4470-1418 / White 2 FC: 4556-7836-2644