@mecarter I think I misunderstood your original post. Reading again, I think the monitor is actually in 1440x900 mode, but you are unhappy the resolution of the framebuffer (and so X) has reduced. That sounds like it is due to overscan adjustment. We now default to not using the edge pixels, as many users complained their TV didn't show them (due to no way of disabling overscan).
Create a file config.txt on boot partition containing "disable_overscan=1".
You can do this in windows, or from Pi:
sudo sh -c "echo disable_overscan=1 >> /boot/config.txt"
should do it. Then reboot.
@rogerdean can you be more specfic. Do you have exactly @mecarter's problem or something different?