Meanwhile, good old forward thinking British Airways are plodding on with their 19 currently serving 737-436's !
I was really excited to travel Club Class in one (Not !) ........in a standard economy class seat with the middle seat blocked and just 2 inches more legroom.
At least Airbus A32* operators have a narrow blocked middle seat with a tray on it.
If it 'ain't broken........ Don't try to mend it !