If they were going to make one it would be WaterBlue. For two GOOD reasons.
1. They are remakes of the first two games released in Japan - Red and Green (I own both games)
2. Blue was the 3rd installment, which was a great improvement to the games
Sorry, but this has been discussed to death, and there have been numerous threads about it. Nintendo has no plans to release a third game for FR/LG. They're working on D/P right now, and I doubt there will be many, if any, GBA games made after that for Pokemon.