Great thread, although I haven't read all the replies properly yet as I need more time....!
To Backwoodsman re...
"H, the key of F is crap for a blues guitarist (unless he puts a capo on F1! Some keys are 'easy' for particular styles on the guitar, and some are 'hard'. If a guitar-player is in standard tuning, he/she will want E, because its 'easy' for blues. Comparatively speaking, and IMN-AHO of course! :-)
J
I KNOWWWWW that's why many guitarists don't like F, lol! You should listen to my attempts to play F on my guitar...ouch, sounds baaaaad!

However, my poor little 48 bass accordion hasn't got a straight B chord unless I make it with other notes so it is a pain trying to play blues in E on it.
If I start a blues jam in F, I do try to yell to guitarists to play in E with capo 1 ...:-)
The black notes 'feel' nicer on a piano as they are all smooth and a little like kitkats (which are a chocolate snack ...in case they are native to Britain!)...   :-)