• ISO 3200: This is likely, although I don't know that Ricoh will do this. Especially since they seem to be holding on to the "less is more" mentality with ISO and MP ratings. Which is great for a small sensor camera.
• 14 MP Sensor: IMO, this is a terrible idea and if they make the sensor 14 MP, then I'll definitely steer far, far away from it. I don't see the point in cramming an extra 4 MP in that same tiny sensor. If it's got an APS-C sensor in it, then maybe. But I still think 10-12 would be plenty even for that. At the current size, 10 MP is plenty.
• 1.8 Lens: The GRD3 has a 1.9 lens already so this would be essentially the same glass. I don't see a change on the way in this department at all.
• GRD1 JPEG Filter: Doubtful. While I'm sure it can be done, it's unlikely that they would. More than likely, they'll be working on new algorithms for the new camera.
Actually you might be surprised. I am hearing some interesting things.