1) When listening to music, what format do you listen to more often,
every time, etc.?

LP - 45%
CD - 45%
Open reel, internet radio, FM, Digital cable radio, cassette, etc - 10%

2) What are the TWO primary differences you hear between the two (If
you do not hear any or the differences are very subtle, please say
so)?

CD - better dynamic range, less background noise, flatter frequency
response
LP - can listen to longer without "listening fatigue", which makes up for
most of its technical shortcomings on a day to day basis, for me.