It's amazing to see the 737 still being built--it's had such a long lifespan.  My favorite of the series is the 737-700, which I've flown cross country on Southwest many times including one six hour flight into strong headwinds.  I like flying at FL410, which Southwest flies often--the sky is such a deep blue color at that altitude and the clouds down below almost look like if they are seen from space.

 

I can't say I favor the 737 over the A320, it's main competitor, both aircraft seem OK to me when I have to fly.  My last flight was two months ago, on an A321 for instance.  But I do enjoy flying in the 737 when I get the chance.  Boeing certainly hit on a good design when they designed it, way back when....

 

John