sweet bike max a mill.
That old bike looks like it should be your little brothers .
It looks like there is a 4-5'' difference in effective top tube length.
I love that stretched out feeling on singlespeeds. I feel that it helps your climbing quite a bit while giving you that nice aggressive xc position. I also feel that you can stay seated longer in that position while climbing.
Your back brake looks a little mal adjusted by the way.